Question

Suppose y varies inversely with X, and y = 48 when x = 3. What is the value of x when y = 24?

NO LINKS OR ANSWERING YOU DON'T KNOW.

a. 3
b. 12
c. 6
d. 24​

Answer 1

C. 6

Explanation:

Recall that inverse variation is given by:

`\displaystyle y=(k)/(x)`

Where k is the constant of variation.

We know that y = 48 when x = 3. Substitute:

`\displaystyle (48)=(k)/((3))`

Solve for k:

`k=3(48)=144`

Hence, our equation is:

`\displaystyle y=(144)/(x)`

We want to find x when y = 24. Substitute:

`\displaystyle (24)/(1)=(144)/(x)`

Cross-multiply:

`24x=144`

Divide both sides by 24. Hence:

`x=6`

Our answer is C.