Week-Men concept

10 weeks

(a) 10 Weeks

750 Men; 20 Weeks = 15000 WeekMen

After 4 weeks, weekmen left =>

750*4=3000

Thus, 15000-3000=12000.

Now Reinforcement increases the Garrison strength to 1200(750+450)

Thus, Weeks to be taken now = 12000Weekmen/1200Men

= 10 Weeks

i think it should be 11 because.....after 4 weeks means 16 weeks remaining...now if 750 men can do it in 20 weeks..then 1500 will have provision for10 weeks...and in our case the men are 1200...so option 1 is ruled out..fourth is also ruled out....option b seems to be correct

28 or 28-16