Question

If y varies inversely as x, and y = 14 when x = 8, find y when x = 7.

Answer 1

y = 16

Explanation:

Given y varies inversely as x then the equation relating them is

y =
`(k)/(x)`

To find k use the condition y = 14 when x = 8, thus

14 =
`(k)/(8)` ( multiply both sides by 8 )

112 = k

y =
`(112)/(x)` ← equation of variation

When x = 7, then

y =
`(112)/(7)` = 16