n = N *2^(rt) n = no of people at a given time N = initial population r = rate of population growth t = time so 59 = 35 * 2^ (r*50) so r = 0.015 so n = 35 * 2^ (20r) = 43.13 million Solution n = N *2^(rt) n = no of people at a given time N = initial population r = rate of population growth t = time so 59 = 35 * 2^ (r*50) so r = 0.015 so n = 35 * 2^ (20r) = 43.13 million.