Question

If y is inversely proportional to x and y = 5, when x = 7, find the value of y when x = 70

Answer 1

y =
`(1)/(2)`

Explanation:

Given y is inversely proportional to 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 = 7, then

5 =
`(k)/(7)` ( multiply both sides by 7 )

35 = k

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

When x = 70, then

y =
`(35)/(70)` =
`(1)/(2)`