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Example Questions
Example Question #1 : How To Find Inverse Variation
A school's tornado shelter has enough food to last 20 children for 6 days. If 24 children ended up taking shelter together, for how many fewer days will the food last?
4
1
6
2
8
1
Because the number of days goes down as the number of children goes up, this problem type is inverse variation. We can solve this problem by the following steps:
20*6=24*x
120=24x
x=120/24
x=5
In this equation, x represents the total number of days that can be weathered by 24 students. This is down from the 6 days that 20 students could take shelter together. So the difference is 1 day less.
Example Question #1 : How To Find Inverse Variation
Find the inverse equation of:
To solve for an inverse, we switch x and y and solve for y. Doing so yields:
Example Question #2 : How To Find Inverse Variation
Find the inverse equation of .
1. Switch the and variables in the above equation.
2. Solve for :
Example Question #3 : How To Find Inverse Variation
When , .
When , .
If varies inversely with , what is the value of when ?
If varies inversely with , .
1. Using any of the two combinations given, solve for :
Using :
2. Use your new equation and solve when :
Example Question #3 : How To Find Inverse Variation
x |
y |
If varies inversely with , what is the value of ?
An inverse variation is a function in the form: or , where is not equal to 0.
Substitute each in .
Therefore, the constant of variation, , must equal 24. If varies inversely as , must equal 24. Solve for .
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