[Ques]: A and B can do a work in 18 days, B and C in 30 days and C and A in 36 days. In how many days will the work be completed, if all three of them work together?
Options:
(A) 360/13 days
(B) 350/13 days
(C) 160/13 days
(D) 260/13 days
(E) 960/13 days
*Ans*: (A)
--CoT--: One day work of A and B = 1/18
One day work of B and C = 1/30
One day work of C and A = 1/36
2(A + B + C) = 1/18 + 1/30 + 1/36
2(A + B + C) = 21/180
(A + B + C) = 13/360
Number of days required = 360/13 days.

[Ques]: 3 candidates in an election and received 1136, 7636 and 11628 votes respectively. What % of the total votes did the winningcandidate got in that election?
Options:
(A) 30%
(B) 59%
(C) 57%
(D) 64%
(E) 69%
*Ans*: (C)
--CoT--: Total number of votes polled = (1136 + 7636 + 11628) = 20400
So, Required percentage = 11628/20400 * 100 = 57%

[Ques]: How many two-digit numbers satisfy this property.: The last digit (unit's digit) of the square of the two-digit number is 2 ?
Options:
(A) 2
(B) 3
(C) 4
(D) 5
(E) 0
*Ans*: (E)
--CoT--: A number ending with 2 can never be a perfect squar

[Ques]: Two pipes A and B can fill a cistern in 20 and 30 minutes respectively, and a third pipe C can empty it in 40 minutes. How long will it take to fill the cistern if all the three are opened at the same time?
Options:
(A) 17 1/9
(B) 17 1/3
(C) 17 1/7
(D) 17 1/9
(E) 17 1/1
*Ans*: (C)
--CoT--: 1/20 + 1/30 - 1/40 = 7/120
120/7 = 17 1/7