Question

Rearrange the formula to make a the subject

Answer 1

Explanation:

p = (3n + a)/(n + a)

Cross multiply

p(n + a) = 3n +a

pn + pa = 3n + a

pa - a = 3n - pn

a(p - 1) = n(3 - p)

Dividing by p - 1

a = n(3 - p)/(p - 1)