This question tests 4th grade ability to solve word problems involving multiplication of a fraction by a whole number, using visual fraction models and equations to represent the problem (CCSS.4.NF.4.c). Word problems involving 'each,' 'per,' or 'every' with a number of groups indicate multiplication—n groups of a/b means $n \times \frac{a}{b}$. To solve, identify the number of groups (n) and the amount per group (a/b), then multiply using the formula $n \times \frac{a}{b} = \frac{n \times a}{b}$. The result should include appropriate units from the problem context (cups, miles, yards, hours, etc.). This problem involves buying pencils where each pencil costs 3/10 dollar and there are 7 pencils, requiring multiplication: $7 \times \frac{3}{10} = \frac{7 \times 3}{10} = \frac{21}{10} = 2 \tfrac{1}{10}$ dollars. Choice C is correct because identifying n=7 pencils and 3/10 per pencil, multiplying: $7 \times 3 = 21$, keeping denominator 10, giving $\frac{21}{10} = 2 \tfrac{1}{10}$ dollars, demonstrating understanding how to recognize multiplication scenarios in word problems and compute fraction × whole number products. Choice A represents an unsimplified fraction like 21/70, which happens when students make arithmetic errors or forget to simplify. To help students: Identify keywords—'each,' 'per,' 'every' indicate the amount for ONE group (the fraction a/b); a number like '3 batches' or '5 days' indicates HOW MANY groups (the multiplier n). Set up equation: n groups × a/b per group = ? Use formula: $n \times \frac{a}{b} = \frac{n \times a}{b}$. Multiply numerator: n × a. Keep denominator: b. Convert improper to mixed if helpful: $\frac{6}{5} = 1 \tfrac{1}{5}$. ALWAYS include units from problem. Draw models: show n groups, each with a/b shaded, count total b-ths. Connect to earlier learning: this is same as 4.NF.4.b formula, now applied in word problems. Watch for: adding instead of multiplying, multiplying denominator by n (wrong), forgetting units, arithmetic errors, and not converting improper fractions when needed for interpretation.

This question tests 4th grade ability to solve word problems involving multiplication of a fraction by a whole number, using visual fraction models and equations to represent the problem (CCSS.4.NF.4.c). Word problems involving 'each,' 'per,' or 'every' with a number of groups indicate multiplication—n groups of a/b means n × (a/b). To solve, identify the number of groups (n) and the amount per group (a/b), then multiply using the formula n × (a/b) = (n × a)/b. The result should include appropriate units from the problem context (cups, miles, yards, hours, etc.). This problem involves building model cars where each car needs 2/9 meter of wire and there are 6 cars, requiring multiplication: 6 × (2/9) = (6 × 2)/9 = 12/9 = 1 1/3 meters. Choice C is correct because it identifies n=6 groups and 2/9 per group, multiplying 6 × 2 = 12, keeping denominator 9, giving 12/9 = 1 1/3 meters. This demonstrates understanding how to recognize multiplication scenarios in word problems and compute fraction × whole number products. Choice D represents adding like 6 + 2/9 = 6 2/9 meters, which happens when students misidentify the operation and add instead of multiplying. To help students: Identify keywords—'each,' 'per,' 'every' indicate the amount for ONE group (the fraction a/b); a number like '3 batches' or '5 days' indicates HOW MANY groups (the multiplier n). Set up equation: n groups × a/b per group = ? Use formula: n × (a/b) = (n × a)/b, multiply numerator n × a, keep denominator b, convert improper to mixed if helpful like 12/9 = 1 1/3, always include units, draw models showing n groups each with a/b shaded, and watch for adding instead of multiplying or arithmetic errors.

This question tests 4th grade ability to solve word problems involving multiplication of a fraction by a whole number, using visual fraction models and equations to represent the problem (CCSS.4.NF.4.c). Word problems involving 'each,' 'per,' or 'every' with a number of groups indicate multiplication—n groups of a/b means n × (a/b). To solve, identify the number of groups (n) and the amount per group (a/b), then multiply using the formula n × (a/b) = (n × a)/b. The result should include appropriate units from the problem context (cups, miles, yards, hours, etc.). This problem involves buying notebooks where each costs 3/10 dollar and there are 7 notebooks, requiring multiplication: 7 × (3/10) = (7 × 3)/10 = 21/10 = 2 1/10 dollars. Choice C is correct because it identifies n=7 groups and 3/10 per group, multiplying 7 × 3 = 21, keeping denominator 10, giving 21/10 = 2 1/10 dollars. This demonstrates understanding how to recognize multiplication scenarios in word problems and compute fraction × whole number products. Choice B represents adding like 7 + 3/10 = 7 3/10 dollars, which happens when students misidentify the operation and add instead of multiplying. To help students: Identify keywords—'each,' 'per,' 'every' indicate the amount for ONE group (the fraction a/b); a number like '3 batches' or '5 days' indicates HOW MANY groups (the multiplier n). Set up equation: n groups × a/b per group = ? Use formula: n × (a/b) = (n × a)/b, multiply numerator n × a, keep denominator b, convert improper to mixed if helpful like 21/10 = 2 1/10, always include units, draw models showing n groups each with a/b shaded, and watch for adding instead of multiplying or arithmetic errors.

This question tests 4th grade ability to solve word problems involving multiplication of a fraction by a whole number, using visual fraction models and equations to represent the problem (CCSS.4.NF.4.c). Word problems involving 'each,' 'per,' or 'every' with a number of groups indicate multiplication—n groups of a/b means $n \times \frac{a}{b}$. To solve, identify the number of groups (n) and the amount per group (a/b), then multiply using the formula $n \times \frac{a}{b} = \frac{n \times a}{b}$. The result should include appropriate units from the problem context (cups, miles, yards, hours, etc.). This problem involves a recipe where each serving uses $1/4$ cup of oil and there are 8 servings, requiring multiplication: $8 \times \frac{1}{4} = \frac{8 \times 1}{4} = \frac{8}{4} = 2$ cups. Choice A is correct because identifying $n=8$ servings and $1/4$ per serving, multiplying: $8 \times 1 = 8$, keeping denominator 4, giving $\frac{8}{4} = 2$ cups, demonstrating understanding how to recognize multiplication scenarios in word problems and compute fraction $\times$ whole number products. Choice B represents dividing instead of multiplying like $\frac{1}{32}$, which happens when students confuse division with multiplication. To help students: Identify keywords—'each,' 'per,' 'every' indicate the amount for ONE group (the fraction a/b); a number like '3 batches' or '5 days' indicates HOW MANY groups (the multiplier n). Set up equation: n groups $\times$ a/b per group = ? Use formula: $n \times \frac{a}{b} = \frac{n \times a}{b}$. Multiply numerator: $n \times a$. Keep denominator: b. Convert improper to mixed if helpful: $6/5 = 1 \frac{1}{5}$. ALWAYS include units from problem. Draw models: show n groups, each with a/b shaded, count total b-ths. Connect to earlier learning: this is same as 4.NF.4.b formula, now applied in word problems. Watch for: adding instead of multiplying, multiplying denominator by n (wrong), forgetting units, arithmetic errors, and not converting improper fractions when needed for interpretation.

This question tests 4th grade ability to solve word problems involving multiplication of a fraction by a whole number, using visual fraction models and equations to represent the problem (CCSS.4.NF.4.c). Word problems involving 'each,' 'per,' or 'every' with a number of groups indicate multiplication—$n$ groups of $\frac{a}{b}$ means $n \times \frac{a}{b}$. To solve, identify the number of groups ($n$) and the amount per group ($\frac{a}{b}$), then multiply using the formula $n \times \frac{a}{b} = \frac{n \times a}{b}$. The result should include appropriate units from the problem context (cups, miles, yards, hours, etc.). This problem involves making posters where each poster uses $\frac{3}{10}$ liter of paint and there are 9 posters, requiring multiplication: $9 \times \frac{3}{10} = \frac{9 \times 3}{10} = \frac{27}{10} = 2 \frac{7}{10}$ liters. Choice B is correct because identifying $n=9$ groups and $\frac{3}{10}$ per group, multiplying: $9 \times 3 = 27$, keeping denominator 10, giving $\frac{27}{10} = 2 \frac{7}{10}$ liters; this demonstrates understanding how to recognize multiplication scenarios in word problems and compute fraction $\times$ whole number products. Choice A represents not simplifying, like $\frac{27}{90}$ from multiplying denominator wrongly, which happens when students incorrectly multiply fractions by multiplying denominators. To help students: Identify keywords—'each,' 'per,' 'every' indicate the amount for ONE group ($\frac{a}{b}$); a number like '3 batches' or '5 days' indicates HOW MANY groups (the multiplier $n$); set up equation: $n$ groups $\times \frac{a}{b}$ per group = ?; use formula: $n \times \frac{a}{b} = \frac{n \times a}{b}$; multiply numerator: $n \times a$; keep denominator: $b$; convert improper to mixed if helpful: $\frac{6}{5} = 1 \frac{1}{5}$; ALWAYS include units from problem; draw models: show $n$ groups, each with $\frac{a}{b}$ shaded, count total b-ths; connect to earlier learning: this is same as 4.NF.4.b formula, now applied in word problems; watch for: adding instead of multiplying, multiplying denominator by $n$ (wrong), forgetting units, arithmetic errors, and not converting improper fractions when needed for interpretation.

This question tests 4th grade ability to solve word problems involving multiplication of a fraction by a whole number, using visual fraction models and equations to represent the problem (CCSS.4.NF.4.c). Word problems involving 'each,' 'per,' or 'every' with a number of groups indicate multiplication—n groups of a/b means n × (a/b). To solve, identify the number of groups (n) and the amount per group (a/b), then multiply using the formula n × (a/b) = (n × a)/b. The result should include appropriate units from the problem context (cups, miles, yards, hours, etc.). This problem involves walking where each day Sofia walks 3/4 mile and there are 6 days, requiring multiplication: 6 × (3/4) = (6 × 3)/4 = 18/4 = 4 1/2 miles. Choice A is correct because it identifies n=6 groups and 3/4 per group, multiplying 6 × 3 = 18, keeping denominator 4, giving 18/4 = 4 1/2 miles. This demonstrates understanding how to recognize multiplication scenarios in word problems and compute fraction × whole number products. Choice C represents an arithmetic error or incorrect multiplication like 9 × 3/4 = 27/4 = 6 3/4 miles, which happens when students use the wrong whole number or make calculation errors. To help students: Identify keywords—'each,' 'per,' 'every' indicate the amount for ONE group (the fraction a/b); a number like '3 batches' or '5 days' indicates HOW MANY groups (the multiplier n). Set up equation: n groups × a/b per group = ? Use formula: n × (a/b) = (n × a)/b, multiply numerator n × a, keep denominator b, convert improper to mixed if helpful like 18/4 = 4 1/2, always include units, draw models showing n groups each with a/b shaded, and watch for adding instead of multiplying or arithmetic errors.

This question tests 4th grade ability to solve word problems involving multiplication of a fraction by a whole number, using visual fraction models and equations to represent the problem (CCSS.4.NF.4.c). Word problems involving 'each,' 'per,' or 'every' with a number of groups indicate multiplication—n groups of a/b means n × (a/b). To solve, identify the number of groups (n) and the amount per group (a/b), then multiply using the formula n × (a/b) = (n × a)/b. The result should include appropriate units from the problem context (cups, miles, yards, hours, etc.). This problem involves walking where each day Sofia walks 2/3 mile and there are 6 days, requiring multiplication: 6 × (2/3) = (6 × 2)/3 = 12/3 = 4 miles. Choice A is correct because identifying n=6 groups and 2/3 per group, multiplying: 6 × 2 = 12, keeping denominator 3, giving 12/3 = 4 miles; this demonstrates understanding how to recognize multiplication scenarios in word problems and compute fraction × whole number products. Choice C represents overcomplicating, such as 6 + 2/3 = 6 2/3, which happens when students misidentify the operation from context and add instead of multiplying. To help students: Identify keywords—'each,' 'per,' 'every' indicate the amount for ONE group (the fraction a/b); a number like '3 batches' or '5 days' indicates HOW MANY groups (the multiplier n); set up equation: n groups × a/b per group = ?; use formula: n × (a/b) = (n × a)/b; multiply numerator: n × a; keep denominator: b; convert improper to mixed if helpful: 6/5 = 1 1/5; ALWAYS include units from problem; draw models: show n groups, each with a/b shaded, count total b-ths; connect to earlier learning: this is same as 4.NF.4.b formula, now applied in word problems; watch for: adding instead of multiplying, multiplying denominator by n (wrong), forgetting units, arithmetic errors, and not converting improper fractions when needed for interpretation.

This question tests 4th grade ability to solve word problems involving multiplication of a fraction by a whole number, using visual fraction models and equations to represent the problem (CCSS.4.NF.4.c). Word problems involving 'each,' 'per,' or 'every' with a number of groups indicate multiplication—n groups of a/b means $n \times \frac{a}{b}$. To solve, identify the number of groups (n) and the amount per group (a/b), then multiply using the formula $n \times \frac{a}{b} = \frac{n \times a}{b}$. The result should include appropriate units from the problem context (cups, miles, yards, hours, etc.). This problem involves practicing piano where each day takes $5/12$ hour and there are 6 days, requiring multiplication: $6 \times \frac{5}{12} = \frac{6 \times 5}{12} = \frac{30}{12} = 2 \frac{1}{2}$ hours. Choice B is correct because identifying n=6 groups and $5/12$ per group, multiplying: $6 \times 5 = 30$, keeping denominator 12, giving $\frac{30}{12} = 2 \frac{1}{2}$ hours; this demonstrates understanding how to recognize multiplication scenarios in word problems and compute fraction × whole number products. Choice A represents not simplifying properly, like $\frac{30}{72}$ from multiplying denominator, which happens when students multiply denominator by n incorrectly. To help students: Identify keywords—'each,' 'per,' 'every' indicate the amount for ONE group (the fraction a/b); a number like '3 batches' or '5 days' indicates HOW MANY groups (the multiplier n); set up equation: n groups × a/b per group = ?; use formula: $n \times \frac{a}{b} = \frac{n \times a}{b}$; multiply numerator: $n \times a$; keep denominator: b; convert improper to mixed if helpful: $\frac{6}{5} = 1 \frac{1}{5}$; ALWAYS include units from problem; draw models: show n groups, each with a/b shaded, count total b-ths; connect to earlier learning: this is same as 4.NF.4.b formula, now applied in word problems; watch for: adding instead of multiplying, multiplying denominator by n (wrong), forgetting units, arithmetic errors, and not converting improper fractions when needed for interpretation.

This question tests 4th grade ability to solve word problems involving multiplication of a fraction by a whole number, using visual fraction models and equations to represent the problem (CCSS.4.NF.4.c). Word problems involving 'each,' 'per,' or 'every' with a number of groups indicate multiplication—n groups of a/b means n × (a/b). To solve, identify the number of groups (n) and the amount per group (a/b), then multiply using the formula n × (a/b) = (n × a)/b. The result should include appropriate units from the problem context (cups, miles, yards, hours, etc.). This problem involves running laps where each lap is 3/4 mile and there are 6 laps, requiring multiplication: 6 × (3/4) = (6 × 3)/4 = 18/4 = 4 1/2 miles. Choice D is correct because identifying n=6 laps and 3/4 per lap, multiplying: 6 × 3 = 18, keeping denominator 4, giving 18/4 = 4 1/2 miles, demonstrating understanding how to recognize multiplication scenarios in word problems and compute fraction × whole number products. Choice A represents an unsimplified fraction like 18/24, which happens when students make arithmetic errors or forget to simplify properly. To help students: Identify keywords—'each,' 'per,' 'every' indicate the amount for ONE group (the fraction a/b); a number like '3 batches' or '5 days' indicates HOW MANY groups (the multiplier n). Set up equation: n groups × a/b per group = ? Use formula: n × (a/b) = (n × a)/b. Multiply numerator: n × a. Keep denominator: b. Convert improper to mixed if helpful: 6/5 = 1 1/5. ALWAYS include units from problem. Draw models: show n groups, each with a/b shaded, count total b-ths. Connect to earlier learning: this is same as 4.NF.4.b formula, now applied in word problems. Watch for: adding instead of multiplying, multiplying denominator by n (wrong), forgetting units, arithmetic errors, and not converting improper fractions when needed for interpretation.

This question tests 4th grade ability to solve word problems involving multiplication of a fraction by a whole number, using visual fraction models and equations to represent the problem (CCSS.4.NF.4.c). Word problems involving 'each,' 'per,' or 'every' with a number of groups indicate multiplication—n groups of a/b means n × (a/b). To solve, identify the number of groups (n) and the amount per group (a/b), then multiply using the formula n × (a/b) = (n × a)/b. The result should include appropriate units from the problem context (cups, miles, yards, hours, etc.). This problem involves watering plants where each plant needs 2/9 liter of water and there are 6 plants, requiring multiplication: 6 × (2/9) = (6 × 2)/9 = 12/9 liters. Choice A is correct because identifying n=6 plants and 2/9 per plant, multiplying: 6 × 2 = 12, keeping denominator 9, giving 12/9 liters, demonstrating understanding how to recognize multiplication scenarios in word problems and compute fraction × whole number products. Choice C represents dividing instead of multiplying like 2/54, which happens when students confuse division with multiplication or make calculation errors. To help students: Identify keywords—'each,' 'per,' 'every' indicate the amount for ONE group (the fraction a/b); a number like '3 batches' or '5 days' indicates HOW MANY groups (the multiplier n). Set up equation: n groups × a/b per group = ? Use formula: n × (a/b) = (n × a)/b. Multiply numerator: n × a. Keep denominator: b. Convert improper to mixed if helpful: 6/5 = 1 1/5. ALWAYS include units from problem. Draw models: show n groups, each with a/b shaded, count total b-ths. Connect to earlier learning: this is same as 4.NF.4.b formula, now applied in word problems. Watch for: adding instead of multiplying, multiplying denominator by n (wrong), forgetting units, arithmetic errors, and not converting improper fractions when needed for interpretation.