Question

The function f(x) varies inversely with x and f(x)=0.5 when x = 0.15.

What is f(x) when x = 2.5?

Answer 1

0.03

Explanation:

Standard equation of inverse variation:

y = k/x

In function notation it is

f(x) = k/x

We are given f(0.15) = 0.5

0.5 = k/0.15

k = 0.5 * 0.15

k = 0.075

The function is

f(x) = 0.075/x

For x = 2.5,

f(2.5) = 0.075/2.5

f(2.5) = 0.03

Answer: 0.03