Question

If y varies inversely as X and Y equals 5 when x equals 3 find X when Y is 15​

Answer 1

x = 1

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 = 5 when x = 3

k = yx = 5 × 3 = 15, thus

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

When y = 15 then

15 =
`(15)/(x)` ( multiply both sides by x )

15x = 15 ( divide both sides by 15 )

x = 1