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A can build a wall in 30 days. B can demolish that wall in 60 days. If A and B work on alternate days, when will the wall be completed? a) 180 days b) 90 days c) 120 days d) 60 days Answer is : C Solution : Given :- 1. A build in => 30 days 2. B demolish in ...

Pipes A and B can fill a cistern in 20 min and 30 min and C can empty it in 15 min. If the three are kept open successively for 1 min each in the order how soon will the cistern be filled? a) 180min b) 90min c) 120 min d) 60 min Answer is : A Solution : Given :- 1. A fills in ...

How many 3 digit numbers sum will have sum 18? a) 51 b) 54 c) 61 d) 64 Answer is : B Solution : Given :- 1. Number is 3 digitnumber. 2. Sum should be 18. What To Find:- How many such numbers exist? Procedure :- Numbers starts with 1 ð 198, 189.................................= 2 numbers Numbers starts with 2 ð 297, 279, 288..........................=...

A, B, C are in GP and M,N,O are in AP, then (O-N)log A + (M-O)log B + (N-M)log C is equal to ? Options : A) (O-N)log ABC B) 0 C) 1 D) none Answer is : B Solution : Given :- 1. A, B, C are in GP. So B2 = A C 2. M,N,O are in AP. So => O-N = N-M = x (assume), then => (O–M) = 2(O–N) = 2x. What...

Compute the number of distinct ways in which 56 toffees can be distributed to 5 persons A,B,C,D and E so that no person receives less than 10 toffees(toffee can not be devided)? Options : A) 210 B) 240 C) 180 D) 230 Answer is : A Solution : Given :- 1. 56 toffees are there 2. 5 members are there 3. no person receives less than 10 toffees What To Find:- No. of...

How many 3 digit numbers are there in which product of their digit is 36. Ex: 236, in this.. product of digit is 36? Options : A) 32 B) 36 C) 21 D) 15 Answer is : C Solution : Given :- 1. Each number is 3 digit number 2. Product Of digits is 36 What To Find:- How many such numbers are there. Procedure :- 1. Factors of 36 are : ...

32400 students login everyday to elitmus website. And stay on the website for 9 minutes. If the access for website is only 18 hours in a day, how many students can be found online at any point of time? Options : A) 324 B) 300 C) 270 D) 200 Answer is : C Solution : Given :- 1. 32400 students login everyday 2. every student stays for 9 minutes. 3. accessible times is 18 hours What...