Question

R is inversely proportional to A.

R = 12 when A = 1.5
a) Work out the value of R when A = 5.
b) Work out the value of A when R = 9

Answer 1

a) R = 3.6

b) A = 2

Explanation:

To find the value, start by modeling the inverse proportionality by using the base equations with the original givens.

y = k/x

12 = k/1.5

18 = k

Now we use that to model the equation

R = 18/A

And we can now use that to solve parts a) and b)

a)

R = 18/A

R = 18/5

R = 3.6

b)

R = 18/A

9 = 18/A

2 = A