Question

The variable z is inversely proportional to x. When x is 16, z has the value 0.875. What is the value of z when x=21

Answer 1

z is inversely proportion to x

⇒ z = k/x where k is a constant.

Find k:

Whe x = 16, z = 0.875

16 = k/0.875

k = 16 x 0.875

k = 14

Therefore z = 14/x

When x = 21, find z:

z = 14/21

z = 2/3

Answer: z = 2/3 or 0.67 (nearest hundredth)