Ques: Three pipes A, B and C can fill a tank from empty to full in 30 minutes, 20 minutes and 10 minutes respectively. When the tank is empty, all the three pipes are opened. A, B and C discharge chemical solutions P, Q and R respectively. What is the proportion of solution R in the liquid in the tank after 3 minutes?
Options:
(A) 5/11
(B) 6/11
(C) 7/11
(D) 8/11
(E) 9/11
Ans: (B)
CoT: Part filled by (A + B + C) in 3 minutes = 3(1/30 + 1/20 + 1/10) = 11/20
Part filled by C in 3 minutes = 3/10
Required ratio = 3/10 * 20/11 = 6/11

Ques: A train 150 meters long completely crosses a 240 meters long bridge in 42 seconds. What is the speed of the train is?
Options:
(A) 32
(B) 33
(C) 88
(D) 66
(E) 09
Ans: (B)
CoT: S = (150 + 240)/42 = 390/42 * 18/5 = 33

Ques: Simple interest on a certain sum is 16 over 25 of the sum. Find the rate per cent and time, if both are equal.
Options:
(A) 8% and 8 years
(B) 6% and 6 years
(C) 10% and 10 years
(D) 12 % and 12 years
(E) None of these
Ans: (A)
CoT: 1625P = PRR/100
R2 = 160025 R = 405 = 8%
Also, time = 8 years

Ques: It is the New Year and Mandy has made a resolution to lose weight this year. She plans to exercise and do yoga. For exercise she plans to workout at the gym and ride her bicycle in the ratio of 2:3 everyday. She will also do yoga in the ratio, yoga:exercise = 2:3. If she rides her bike for 10 minutes, how much time will she spend doing yoga? (rounded to minutes)
Options:
(A) 10 min.
(B) 41 min.
(C) 17 min.
(D) 23 min.
(E) 25 min.
Ans: (C)
CoT: The ratio is 2:3 = gym:ride, so (10)(3/2) = 15 minutes at the gym, and 15 + 10 = 25 minutes exercise, so (2/3)(25) = 17 minutes yoga.