q: A and B can do a work in 12 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) 189/13 days
(B) 188/13 days
(C) 180/13 days
(D) 180/17 days
(E) 280/13 days
a: Stream of consciousness: One day work of A and B = 1/12
One day work of B and C = 1/30
One day work of C and A = 1/36
2(A + B + C) = 1/12 + 1/30 + 1/36
2(A + B + C) = 13/90
(A + B + C) = 13/180
Number of days required = 180/13 days. The answer is (C).

question: 30 pens and 75 pencils were purchased for 750. If the average price of a pencil was 2.00, find the average price of a pen.
Options:
(A) 20
(B) 11
(C) 12
(D) 13
(E) 14
answer: Stream of consciousness: Since average price of a pencil = 2
Price of 75 pencils = 150
Price of 30 pens = (750 150) = 600
Average price of a pen = 60060 = 20 The answer is (A).

q: By how much is 70% of 120 greater than 35% of 200.
Options:
(A) 15
(B) 14
(C) 13
(D) 16
(E) 17
a: Stream of consciousness: (70/100) * 120 (35/100) * 200
84 - 70 = 14 The answer is (B).

question: The average length of the sides of triangle ABC is 12. What is the perimeter of triangle ABC?
Options:
(A) 4
(B) 6
(C) 12
(D) 24
(E) 36
answer: Stream of consciousness: (average) = (perimeter)/3;
12 = (perimeter)/3;
(perimeter) = 36. The answer is (E).

q: A pipe can fill a cistern in 20 minutes whereas the cistern when fill can be emptied by a leak in 28 minutes. When both pipes are opened, find when the cistern will be full?
Options:
(A) 17 minutes
(B) 87 minutes
(C) 70 minutes
(D) 27 minutes
(E) 11 minutes
a: Stream of consciousness: 1/20 - 1/28 = 1/70
70 minutes The answer is (C).

q: Find the smallest number which should be multiplied with 1152 to make it a perfect square.
Options:
(A) 2
(B) 1
(C) 3
(D) 5
(E) 6
a:
Stream of consciousness: 1152 = 2*2*2*2*2*2*2*3*3
Required smallest number = 2
2 is the smallest number which should be multiplied with 1152 to make it a perfect square. The answer is (A).