Question

Suppose y varies inversely with x, and y = 25 when x = 1/5. What is the value of y when x = 5 ?

Answer 1

y = 1

Explanation:

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

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

To find k use the condition y = 25 when x =
`(1)/(5)` , then

25 =
`(k)/((1)/(5) )` = 5k ( divide both sides by 5 )

5 = k

y =
`(5)/(x)` ← equation of variation

When x = 5, then

y =
`(5)/(5)` = 1