Question

What is the value of A when r=9 in inverse proportions

Answer 1

3.6 and 2

Explanation:

Given R is inversely proportional to A then the equation relating them is

R =
`(k)/(A)` ← k is the constant of proportion

To find k use the condition R = 12 when A = 1.5, that is

12 =
`(k)/(1.5)` ( multiply both sides by 1.5 )

18 = k

R =
`(18)/(A)` ← equation of proportion

(a)

when A = 5, then

R =
`(18)/(5)` = 3.6

(b)

when R = 9, then

9 =
`(18)/(A)` ( multiply both sides by A )

9A = 18 ( divide both sides by 9 )

A = 2