Question

If y varies inversely as x and y = 18 when x = 4, what is y when x = 242

Answer 1

y =
`(36)/(121)`

Explanation:

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

y =
`(k)/(x)` ← k is the constant of variation

To find k use the condition y = 18 when x = 4

k = yx = 18 × 4 = 72, so

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

When x = 242, then

y =
`(72)/(242)` =
`(36)/(121)`