As given r = r(max)/2
k= 50
r(max) = 0.5
By substituting the values,
r= 0.5/2 = 0.25
You have to use following equation to get a value of N
r = r(max) ( 1- N/K)
N/k = 1 - r/r(max)
N/K = 1 - 0.5 = 0.5
N= 50 × 0.5 = 25
