Q. Assuming the Putnam model and given S = 100,000 C = 5000 and D0 = 15 calculate the development time td.
Ans: In Putnam model
(S/C ) ^{3} = D_{0}t_{d}^{7}
lhs = 20^{3 }= 8000
t_{d}^{7} = 8000/ 15
t_{d} is seventh root of 533.33