SAT Math : How to find inverse variation

Study concepts, example questions & explanations for SAT Math

varsity tutors app store varsity tutors android store varsity tutors amazon store varsity tutors ibooks store

Example Questions

Example Question #11 :Algebraic Fractions

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?

Possible Answers:

1

8

2

6

4

Correct answer:

1

Explanation:

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:

Possible Answers:

Correct answer:

Explanation:

To solve for an inverse, we switch x and y and solve for y. Doing so yields:

Example Question #7 :Algebraic Fractions

Find the inverse equation of.

Possible Answers:

Correct answer:

Explanation:

1. Switch theandvariables in the above equation.

2. Solve for:

Example Question #1 :Algebraic Fractions

When,.

When,.

Ifvaries inversely with, what is the value ofwhen?

Possible Answers:

Correct answer:

Explanation:

Ifvaries inversely with,.

1. Using any of the twocombinations given, solve for:

Using:

2. Use your new equationand solve when:

Example Question #1 :How To Find Inverse Variation

x

y

Ifvaries inversely with, what is the value of?

Possible Answers:

Correct answer:

Explanation:

An inverse variation is a function in the form:or, whereis not equal to 0.

Substitute eachin.

Therefore, the constant of variation,, must equal 24. Ifvaries inversely as,must equal 24. Solve for.

Learning Tools by Varsity Tutors