Question

If y varies inversely as x, and y = 10 when x = 20,
find x when y = 16.

Answer 1

12.5

Explanation:

y varies inversely as x.

y = k/x

10 = k/20

200 = k

The constant proportion k is 200.

16 = 200/x

Cross multiply.

200 = 16x

200/16 = x

x = 12.5