A tank is filled in 5 hours by three pipes A,B and C The pipe C is twice as fast as B and B is twice as fast as A How much time will pipe A alone take to fill the tank?
20 hours
25 hours
35 hours
None of these
Find the least number of five digits which when divided by 40, 60, and 75 , leave remainders 31 ,51 and 66 respectively .
10196
10199
10197
10191