Question

Suppose p varies directly with d and p=3 when d=5. What is the value of d when p=12

Answer 1

Answer: d is 20

Explanation:

`{ \rm{p \: \alpha \: d}} \\ \\ { \rm{p = kd}}`

k is a constant of proportionality

• When p = 3, d = 5.

`{ \rm{3 = (k * 5)}} \\ \\ { \rm{k = (3)/(5) }}`

• Therefore, equation becomes;

`{ \rm{p = (3)/(5) d}}`

• Let's find d when p is 12;

`{ \rm{12 = (3)/(5)d }} \\ \\ { \rm{d = (12 * 5)/(3) }} \\ \\ { \underline{ \underline{ \rm{ \: \: d = 20 \: \: }}}}`