Common Core: High School - Statistics and Probability : Making Inferences & Justifying Conclusions

Study concepts, example questions & explanations for Common Core: High School - Statistics and Probability

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Example Questions

Example Question #1 : Making Inferences & Justifying Conclusions

A car designer wants to know if customers prefer automatic or manual transmissions in cars. The designer hires a market research team to randomly sample and survey the preferences of potential car buyers in three major cities: New York, Chicago, and Los Angeles.

The data collected in this survey would be best described as which of the following?

Possible Answers:

Population parameter

None of these

Sample statistic

Population statistic

Sample parameter

Correct answer:

Sample statistic

Explanation:

Solving questions related to this standard requires an understanding of definitions common to statistics. Specifically, this question is testing your knowledge of the difference between two fundamental statistical concepts: sample statistics and population parameters. Let's begin by discussing the differences between these two measures. Later, we will use this information to solve the problem.

First let's discuss what is meant by the term population. In statistics, a "population" is described as the entire group that is to be studied. An example of a population in the natural sciences would be every giant panda of the species Ailuropoda melanoleuca in the wild (1864 individuals according to the World Wildlife Foundation)—not captivity. Now, let's identify what is meant by the term population parameter. A "population parameter" is a statistic that is found by sampling the entire population. For example, the mean weight of the entire wild population of giant pandas in the world would be an example of a population parameter (i.e. the mean weight of all 1864 pandas). Next, we will discuss sample populations and statistics.

A "sample" is the subset of a population that is being studied. For example, researchers for a university want to study giant pandas in the wild but can only access a group of 100 pandas sampled in Sichuan, China. Data collected from this particular study would be known as a sample statistic (e.g. the mean weight of pandas in the Sichuan region). It is important to note that the external validity of some sample statistics are hindered. The external validity of a statistic is its ability to be applied to other samples and remain valid. If locals fed pandas in the Sichuan region, then their mean weight may be greater than those of the southern or northern regions. In this instance, the mean would not be representative of other populations of giant pandas. 

Last, we should note that certain sample populations are better than others at predicting population parameters. A population parameter can be considered to be the true statistic of a given population while a sample statistic is only an estimate of a part or subset of the population. Simple random samples are good predictors of population parameters and can be used to estimate them. They are collected when every member in a population has an equal chance of being chosen (e.g. randomly selecting 100 of the 1864 pandas in the world). 

 Now, let's use this information to solve the question. The designer wants to know the preferences of potential car buyers; however, he only samples three major US cities. The data collected from this survey is an example of a sample statistic. It did not gather information from all of the potential car buyers for the particular company; therefore, the best answer is "sample statistic."

Example Question #2 : Making Inferences & Justifying Conclusions

Two college students, Joe and Melissa, are playing a tabletop role-playing game where snake eyes (a value of one on each of the two dice) allows one opponent to effectively attack the other. After three turns, Joe roles snake eyes three times consecutively while Melissa has not rolled it once. She begins to believe that Joe is using loaded dice, which would give him an unfair advantage. She decides to test this theory by rolling her fair dice three times in a row for sixty trials. Melissa knows that the probability of rolling snake eyes is fairly low; furthermore, after sixty trials she only roles snake eyes two times in a row. 

Which of the following will Melissa most likely conclude?

Possible Answers:

Melissa cannot tell if Joe is using loaded or fair dice

Joe is using fair dice

Joe has tricked her by using loaded dice

Melissa miscalculated the probability of rolling snake eyes

Correct answer:

Joe has tricked her by using loaded dice

Explanation:

This question is asking us to use a simulation in order to determine whether or not an observed phenomenon is statistically probable. We will do this by creating and testing a hypothesis. Afterwards, we can use our collected data to make a conclusion as to whether or not Joe is using fair dice in this scenario. 

Hypotheses are "if/then" statements that represent an inference or educated guess regarding a particular phenomenon. They are tested through experimentation. The results of an experiment will reveal if a hypothesis can be supported or not. At this point, it is important tot note that a hypothesis can never be proven: experimentation can only support or refute a hypothesis. Even scientific theories cannot be proven they only have a mass of supporting studies to add to their scientific validity. 

Before we solve this problem, we should review the scientific process. In the scientific method we observe a phenomenon, gather background information, develop a tentative explanation (i.e. a hypothesis), test this explanation through the observation and manipulation of variables, and, finally, we create conclusions based upon experimentation. These conclusions will either support or refute the hypothesis.

Now, let's use this information to solve the problem regarding whether or not Joe is using fair dice. In this problem, Melissa noticed that Joe rolled snake eyes three times in a row. She gathered background information and identified the following probability calculations:

From this information, she realized that the probability of rolling snake eyes three times in a row is very low. Using this information, Melissa created an experiment, In this experiment, she rolled her known fair dice three times in a row for sixty trials. In these sixty trials she was only able to roll snake eyes in a row two times. From this information she was able to make the following conclusion: "Joe has tricked her by using loaded dice."

In this lesson we have learned how to use simulations and the scientific method in order to determine whether or not an event is the product of random chance or manipulation (i.e. Joe tricking Melissa with loaded dice).

Example Question #1 : Making Inferences & Justifying Conclusions

Two college students, Joe and Melissa, are playing a tabletop role-playing game where snake eyes (a value of one on each of the two dice) allows one opponent to effectively attack the other. After three turns, Joe roles snake eyes three times while Melissa has not rolled it once. She begins to believe that Joe is using loaded dice, which would give him an unfair advantage. She decides to test this theory by rolling her fair dice three times in a row for sixty trials. Melissa knows that the probability of rolling snake eyes is fairly low; furthermore, after sixty trials she only roles snake eyes two times in a row. 

Which of the following will Melissa most likely conclude?

Possible Answers:

Melissa miscalculated the probability of rolling snake eyes

Joe is using fair dice

Joe has tricked her by using loaded dice

Melissa cannot tell if Joe is using loaded or fair dice

Correct answer:

Joe has tricked her by using loaded dice

Explanation:

This question is asking us to use a simulation in order to determine whether or not an observed phenomenon is statistically probable. We will do this by creating and testing a hypothesis. Afterwards, we can use our collected data to make a conclusion as to whether or not Joe is using fair dice in this scenario. 

Hypotheses are "if/then" statements that represent an inference or educated guess regarding a particular phenomenon. They are tested through experimentation. The results of an experiment will reveal if a hypothesis can be supported or not. At this point, it is important tot note that a hypothesis can never be proven: experimentation can only support or refute a hypothesis. Even scientific theories cannot be proven they only have a mass of supporting studies to add to their scientific validity. 

Before we solve this problem, we should review the scientific process. In the scientific method we observe a phenomenon, gather background information, develop a tentative explanation (i.e. a hypothesis), test this explanation through the observation and manipulation of variables, and, finally, we create conclusions based upon experimentation. These conclusions will either support or refute the hypothesis.

Now, let's use this information to solve the problem regarding whether or not Joe is using fair dice. In this problem, Melissa noticed that Joe rolled snake eyes three times in a row. She gathered background information and identified the following probability calculations:

From this information, she realized that the probability of rolling snake eyes three times in a row is very low. Using this information, Melissa created an experiment, In this experiment, she rolled her known fair dice three times in a row for sixty trials. In these sixty trials she was only able to roll snake eyes in a row two times. From this information she was able to make the following conclusion: "Joe has tricked her by using loaded dice."

In this lesson we have learned how to use simulations and the scientific method in order to determine whether or not an event is the product of random chance or manipulation (i.e. Joe tricking Melissa with loaded dice).

Example Question #2 : Making Inferences & Justifying Conclusions

Two college students, Joe and Melissa, are playing a tabletop role-playing game where snake eyes (a value of one on each of the two dice) allows one opponent to effectively attack the other. After five turns Joe roles snake eyes five times consecutively while Melissa has not rolled it once. She begins to believe that Joe is using loaded dice, which would give him an unfair advantage. She decides to test this theory by rolling her fair dice five times in a row for sixty trials. Melissa knows that the probability of rolling snake eyes is fairly low; furthermore, after sixty trials she only roles snake eyes two times in a row.

Which of the following will Melissa most likely conclude?

Possible Answers:

Melissa cannot tell if Joe is using loaded or fair dice

Joe has tricked her by using loaded dice

Joe is using fair dice

Melissa miscalculated the probability of rolling snake eyes

Correct answer:

Joe has tricked her by using loaded dice

Explanation:

This question is asking us to use a simulation in order to determine whether or not an observed phenomenon is statistically probable. We will do this by creating and testing a hypothesis. Afterwards, we can use our collected data to make a conclusion as to whether or not Joe is using fair dice in this scenario.

Hypotheses are 'if/then' statements that represent an inference or educated guess regarding a particular phenomenon. They are tested through experimentation. The results of an experiment will reveal if a hypothesis can be supported or not. At this point, it is important tot note that a hypothesis can never be proven: experimentation can only support or refute a hypothesis. Even scientific theories cannot be proven they only have a mass of supporting studies to add to their scientific validity.

Before we solve this problem, we should review the scientific process. In the scientific method we observe a phenomenon, gather background information, develop a tentative explanation (i.e. a hypothesis), test this explanation through the observation and manipulation of variables, and, finally, we create conclusions based upon experimentation. These conclusions will either support or refute the hypothesis.

Now, let's use this information to solve the problem regarding whether or not Joe is using fair dice. In this problem, Melissa noticed that Joe rolled snake eyes three times in a row. She gathered background information and identified the following probability calculations:

From this information, she realized that the probability of rolling snake eyes five times in a row is very low. Using this information, Melissa created an experiment, In this experiment, she rolled her known fair dice five times in a row for sixty trials. In these sixty trials she was only able to roll snake eyes in a row two times. From this information she was able to make the following conclusion: 'Joe has tricked her by using loaded dice.'

In this lesson we have learned how to use simulations and the scientific method in order to determine whether or not an event is the product of random chance or manipulation (i.e. Joe tricking Melissa with loaded dice).

 

 

 

Example Question #4 : Simulations For Models: Ccss.Math.Content.Hss Ic.A.2

Two college students, Joe and Melissa, are playing a tabletop role-playing game where snake eyes (a value of one on each of the two dice) allows one opponent to effectively attack the other.After four turns Joe roles snake eyes four times consecutively while Melissa has not rolled it once. She begins to believe that Joe is using loaded dice, which would give him an unfair advantage.She decides to test this theory by rolling her fair dice four times in a row for sixty trials. Melissa knows that the probability of rolling snake eyes is fairly low; furthermore, after sixty trials she only roles snake eyes two times in a row.

Which of the following will Melissa most likely conclude?

Possible Answers:

Joe is using fair dice

Melissa cannot tell if Joe is using loaded or fair dice

Melissa miscalculated the probability of rolling snake eyes

Joe has tricked her by using loaded dice

Correct answer:

Joe has tricked her by using loaded dice

Explanation:

This question is asking us to use a simulation in order to determine whether or not an observed phenomenon is statistically probable. We will do this by creating and testing a hypothesis. Afterwards, we can use our collected data to make a conclusion as to whether or not Joe is using fair dice in this scenario.

Hypotheses are 'if/then' statements that represent an inference or educated guess regarding a particular phenomenon. They are tested through experimentation. The results of an experiment will reveal if a hypothesis can be supported or not. At this point, it is important tot note that a hypothesis can never be proven: experimentation can only support or refute a hypothesis. Even scientific theories cannot be proven they only have a mass of supporting studies to add to their scientific validity.

Before we solve this problem, we should review the scientific process. In the scientific method we observe a phenomenon, gather background information, develop a tentative explanation (i.e. a hypothesis), test this explanation through the observation and manipulation of variables, and, finally, we create conclusions based upon experimentation. These conclusions will either support or refute the hypothesis.

Now, let's use this information to solve the problem regarding whether or not Joe is using fair dice. In this problem, Melissa noticed that Joe rolled snake eyes three times in a row. She gathered background information and identified the following probability calculations:

From this information, she realized that the probability of rolling snake eyes four times in a row is very low. Using this information, Melissa created an experiment, In this experiment, she rolled her known fair dice four times in a row for sixty trials. In these sixty trials she was only able to roll snake eyes in a row two times. From this information she was able to make the following conclusion: 'Joe has tricked her by using loaded dice.'

In this lesson we have learned how to use simulations and the scientific method in order to determine whether or not an event is the product of random chance or manipulation (i.e. Joe tricking Melissa with loaded dice).

 

Example Question #3 : Making Inferences & Justifying Conclusions

Two college students, Joe and Melissa, are playing a tabletop role-playing game where snake eyes (a value of one on each of the two dice) allows one opponent to effectively attack the other. After six turns Joe roles snake eyes six times consecutively while Melissa has not rolled it once. She begins to believe that Joe is using loaded dice, which would give him an unfair advantage. She decides to test this theory by rolling her fair dice six times in a row for sixty trials. Melissa knows that the probability of rolling snake eyes is fairly low; furthermore, after sixty trials she only roles snake eyes two times in a row.

Which of the following will Melissa most likely conclude?

 

Possible Answers:

Melissa cannot tell if Joe is using loaded or fair dice

Melissa miscalculated the probability of rolling snake eyes

Joe has tricked her by using loaded dice

 Joe is using fair dice

Correct answer:

Joe has tricked her by using loaded dice

Explanation:

This question is asking us to use a simulation in order to determine whether or not an observed phenomenon is statistically probable. We will do this by creating and testing a hypothesis. Afterwards, we can use our collected data to make a conclusion as to whether or not Joe is using fair dice in this scenario.

Hypotheses are 'if/then' statements that represent an inference or educated guess regarding a particular phenomenon. They are tested through experimentation. The results of an experiment will reveal if a hypothesis can be supported or not. At this point, it is important tot note that a hypothesis can never be proven: experimentation can only support or refute a hypothesis. Even scientific theories cannot be proven they only have a mass of supporting studies to add to their scientific validity.

Before we solve this problem, we should review the scientific process. In the scientific method we observe a phenomenon, gather background information, develop a tentative explanation (i.e. a hypothesis), test this explanation through the observation and manipulation of variables, and, finally, we create conclusions based upon experimentation. These conclusions will either support or refute the hypothesis.

Now, let's use this information to solve the problem regarding whether or not Joe is using fair dice. In this problem, Melissa noticed that Joe rolled snake eyes three times in a row. She gathered background information and identified the following probability calculations:

From this information, she realized that the probability of rolling snake eyes six times in a row is very low. Using this information, Melissa created an experiment, In this experiment, she rolled her known fair dice six times in a row for sixty trials. In these sixty trials she was only able to roll snake eyes in a row two times. From this information she was able to make the following conclusion: 'Joe has tricked her by using loaded dice.'

In this lesson we have learned how to use simulations and the scientific method in order to determine whether or not an event is the product of random chance or manipulation (i.e. Joe tricking Melissa with loaded dice).

 

Example Question #4 : Making Inferences & Justifying Conclusions

Two college students, Joe and Melissa, are playing a tabletop role-playing game where snake eyes (a value of one on each of the two dice) allows one opponent to effectively attack the other. After seven turns Joe roles snake eyes seven times consecutively while Melissa has not rolled it once. She begins to believe that Joe is using loaded dice, which would give him an unfair advantage. She decides to test this theory by rolling her fair dice seven times in a row for sixty trials. Melissa knows that the probability of rolling snake eyes is fairly low; furthermore, after sixty trials she only roles snake eyes two times in a row.

Which of the following will Melissa most likely conclude?

Possible Answers:

Melissa miscalculated the probability of rolling snake eyes

Joe is using fair dice

Joe has tricked her by using loaded dice

Melissa cannot tell if Joe is using loaded or fair dice

Correct answer:

Joe has tricked her by using loaded dice

Explanation:

This question is asking us to use a simulation in order to determine whether or not an observed phenomenon is statistically probable. We will do this by creating and testing a hypothesis. Afterwards, we can use our collected data to make a conclusion as to whether or not Joe is using fair dice in this scenario.

Hypotheses are 'if/then' statements that represent an inference or educated guess regarding a particular phenomenon. They are tested through experimentation. The results of an experiment will reveal if a hypothesis can be supported or not. At this point, it is important tot note that a hypothesis can never be proven: experimentation can only support or refute a hypothesis. Even scientific theories cannot be proven they only have a mass of supporting studies to add to their scientific validity.

Before we solve this problem, we should review the scientific process. In the scientific method we observe a phenomenon, gather background information, develop a tentative explanation (i.e. a hypothesis), test this explanation through the observation and manipulation of variables, and, finally, we create conclusions based upon experimentation. These conclusions will either support or refute the hypothesis.

Now, let's use this information to solve the problem regarding whether or not Joe is using fair dice. In this problem, Melissa noticed that Joe rolled snake eyes three times in a row. She gathered background information and identified the following probability calculations:

From this information, she realized that the probability of rolling snake eyes seven times in a row is very low. Using this information, Melissa created an experiment, In this experiment, she rolled her known fair dice seven times in a row for sixty trials. In these sixty trials she was only able to roll snake eyes in a row two times. From this information she was able to make the following conclusion: 'Joe has tricked her by using loaded dice.'

In this lesson we have learned how to use simulations and the scientific method in order to determine whether or not an event is the product of random chance or manipulation (i.e. Joe tricking Melissa with loaded dice).

 

 

Example Question #1 : Simulations For Models: Ccss.Math.Content.Hss Ic.A.2

Two college students, Joe and Melissa, are playing a tabletop role-playing game where snake eyes (a value of one on each of the two dice) allows one opponent to effectively attack the other. After eight turns Joe roles snake eyes eight times consecutively while Melissa has not rolled it once. She begins to believe that Joe is using loaded dice, which would give him an unfair advantage. She decides to test this theory by rolling her fair dice eight times in a row for sixty trials. Melissa knows that the probability of rolling snake eyes is fairly low; furthermore, after sixty trials she only roles snake eyes two times in a row.

Which of the following will Melissa most likely conclude?

 

Possible Answers:

Joe has tricked her by using loaded dice

Joe is using fair dice

Melissa miscalculated the probability of rolling snake eyes

Melissa cannot tell if Joe is using loaded or fair dice

Correct answer:

Joe has tricked her by using loaded dice

Explanation:

This question is asking us to use a simulation in order to determine whether or not an observed phenomenon is statistically probable. We will do this by creating and testing a hypothesis. Afterwards, we can use our collected data to make a conclusion as to whether or not Joe is using fair dice in this scenario.

Hypotheses are 'if/then' statements that represent an inference or educated guess regarding a particular phenomenon. They are tested through experimentation. The results of an experiment will reveal if a hypothesis can be supported or not. At this point, it is important tot note that a hypothesis can never be proven: experimentation can only support or refute a hypothesis. Even scientific theories cannot be proven they only have a mass of supporting studies to add to their scientific validity.

Before we solve this problem, we should review the scientific process. In the scientific method we observe a phenomenon, gather background information, develop a tentative explanation (i.e. a hypothesis), test this explanation through the observation and manipulation of variables, and, finally, we create conclusions based upon experimentation. These conclusions will either support or refute the hypothesis.

Now, let's use this information to solve the problem regarding whether or not Joe is using fair dice. In this problem, Melissa noticed that Joe rolled snake eyes three times in a row. She gathered background information and identified the following probability calculations:

From this information, she realized that the probability of rolling snake eyes eight times in a row is very low. Using this information, Melissa created an experiment, In this experiment, she rolled her known fair dice eight times in a row for sixty trials. In these sixty trials she was only able to roll snake eyes in a row two times. From this information she was able to make the following conclusion: 'Joe has tricked her by using loaded dice.'

In this lesson we have learned how to use simulations and the scientific method in order to determine whether or not an event is the product of random chance or manipulation (i.e. Joe tricking Melissa with loaded dice).

 

 

Example Question #7 : Simulations For Models: Ccss.Math.Content.Hss Ic.A.2

Two college students, Joe and Melissa, are playing a tabletop role-playing game where snake eyes (a value of one on each of the two dice) allows one opponent to effectively attack the other. After nine turns Joe roles snake eyes nine times consecutively while Melissa has not rolled it once. She begins to believe that Joe is using loaded dice, which would give him an unfair advantage. She decides to test this theory by rolling her fair dice nine times in a row for sixty trials. Melissa knows that the probability of rolling snake eyes is fairly low; furthermore, after sixty trials she only roles snake eyes two times in a row.

Which of the following will Melissa most likely conclude?

 

Possible Answers:

Joe has tricked her by using loaded dice

Melissa cannot tell if Joe is using loaded or fair dice

Joe is using fair dice

Melissa miscalculated the probability of rolling snake eyes

Correct answer:

Joe has tricked her by using loaded dice

Explanation:

This question is asking us to use a simulation in order to determine whether or not an observed phenomenon is statistically probable. We will do this by creating and testing a hypothesis. Afterwards, we can use our collected data to make a conclusion as to whether or not Joe is using fair dice in this scenario.

Hypotheses are 'if/then' statements that represent an inference or educated guess regarding a particular phenomenon. They are tested through experimentation. The results of an experiment will reveal if a hypothesis can be supported or not. At this point, it is important tot note that a hypothesis can never be proven: experimentation can only support or refute a hypothesis. Even scientific theories cannot be proven they only have a mass of supporting studies to add to their scientific validity.

Before we solve this problem, we should review the scientific process. In the scientific method we observe a phenomenon, gather background information, develop a tentative explanation (i.e. a hypothesis), test this explanation through the observation and manipulation of variables, and, finally, we create conclusions based upon experimentation. These conclusions will either support or refute the hypothesis.

Now, let's use this information to solve the problem regarding whether or not Joe is using fair dice. In this problem, Melissa noticed that Joe rolled snake eyes three times in a row. She gathered background information and identified the following probability calculations:

From this information, she realized that the probability of rolling snake eyes nine times in a row is very low. Using this information, Melissa created an experiment, In this experiment, she rolled her known fair dice nine times in a row for sixty trials. In these sixty trials she was only able to roll snake eyes in a row two times. From this information she was able to make the following conclusion: 'Joe has tricked her by using loaded dice.'

In this lesson we have learned how to use simulations and the scientific method in order to determine whether or not an event is the product of random chance or manipulation (i.e. Joe tricking Melissa with loaded dice).

 

 

Example Question #1 : Making Inferences & Justifying Conclusions

Two college students, Joe and Melissa, are playing a tabletop role-playing game where snake eyes (a value of one on each of the two dice) allows one opponent to effectively attack the other. After ten turns Joe roles snake eyes ten times consecutively while Melissa has not rolled it once. She begins to believe that Joe is using loaded dice, which would give him an unfair advantage. She decides to test this theory by rolling her fair dice ten times in a row for sixty trials. Melissa knows that the probability of rolling snake eyes is fairly low; furthermore, after sixty trials she only roles snake eyes two times in a row.

Which of the following will Melissa most likely conclude?

 

Possible Answers:

Melissa cannot tell if Joe is using loaded or fair dice

Melissa miscalculated the probability of rolling snake eyes

Joe has tricked her by using loaded dice

Joe is using fair dice

Correct answer:

Joe has tricked her by using loaded dice

Explanation:

This question is asking us to use a simulation in order to determine whether or not an observed phenomenon is statistically probable. We will do this by creating and testing a hypothesis. Afterwards, we can use our collected data to make a conclusion as to whether or not Joe is using fair dice in this scenario.

Hypotheses are 'if/then' statements that represent an inference or educated guess regarding a particular phenomenon. They are tested through experimentation. The results of an experiment will reveal if a hypothesis can be supported or not. At this point, it is important tot note that a hypothesis can never be proven: experimentation can only support or refute a hypothesis. Even scientific theories cannot be proven they only have a mass of supporting studies to add to their scientific validity.

Before we solve this problem, we should review the scientific process. In the scientific method we observe a phenomenon, gather background information, develop a tentative explanation (i.e. a hypothesis), test this explanation through the observation and manipulation of variables, and, finally, we create conclusions based upon experimentation. These conclusions will either support or refute the hypothesis.

Now, let's use this information to solve the problem regarding whether or not Joe is using fair dice. In this problem, Melissa noticed that Joe rolled snake eyes three times in a row. She gathered background information and identified the following probability calculations:

From this information, she realized that the probability of rolling snake eyes ten times in a row is very low. Using this information, Melissa created an experiment, In this experiment, she rolled her known fair dice ten times in a row for sixty trials. In these sixty trials she was only able to roll snake eyes in a row two times. From this information she was able to make the following conclusion: 'Joe has tricked her by using loaded dice.'

In this lesson we have learned how to use simulations and the scientific method in order to determine whether or not an event is the product of random chance or manipulation (i.e. Joe tricking Melissa with loaded dice).

 

 

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