Rationale: 1/9 + 1/18 = 1/6
6/1 = 6 days
The answer: (A)
Question: A and B complete a work in 9 days. A alone can do it in 18 days. If both together can do the work in how many days?
Options:
(A) 6 days
(B) 8 days
(C) 5 days
(D) 7 days
(E) 15 days
Reasoning: (10/100)Workers = 16 = > number of workers = 160
(30/100)*Workers = x+16 = > x = 48
Ans: (B)
Question: In an office, 30 percent of the workers have at least 5 years of service, and a total of 16 workers have at least 10 years of service. If 90 percent of the workers have fewer than 10 years of service, how many of the workers have at least 5 but fewer than 10 years of service?
Options:
(A) 480
(B) 48
(C) 50
(D) 144
(E) 160
Rationale: 27 Seconds
Distance travelled = 140 + 310m = 450m
Speed = 60 * 5/8 = 50/3m
Time = 450 * 3/50 = 27 Seconds
The answer: (E)
Question: A bullet train 140 m long is running at 60 kmph. In how much time will it pass a platform 310 m long?
Options:
(A) 34 Seconds
(B) 22 Seconds
(C) 41 Seconds
(D) 24 Seconds
(E) 27 Seconds
Reasoning: Correct Answer: (E)
Let's go through each answer choice: (A) can never be true, since no negative is greater than a positive. (B) doesn't have to be true consider what would happen if x = -2 and y = 1. (C) can never be true, as x^3 must be negative, and y^2 must be positive. (D) can never be true, since if x < 0, -x is the same thing as |x|, and |x| > y. (E) can be manipulated by multiplying both sides by -1, which gives us x > y. Remember that x < 0, so x = |x|, and y is positive, so |y| = y. Thus x > y is the same statement as |x| > |y|, and (A) must be true.
Ans: (A)
Question: If x>0, y>0, and |x| > |y|, which of the following must be true?
Options:
(A) x > y
(B) y^2 > x^2
(C) x^3 > y^2
(D) x < y
(E) x < y
Rationale: 1/8 + 1/24 = 1/6
6 * 2 = 12
The answer: (B)
Question: Pipes A and B can fill a cistern in 8 and 24 minutes respectively. They are opened an alternate minutes. Find how many minutes, the cistern shall be full?
Options:
(A) 11
(B) 12
(C) 99
(D) 75
(E) 72
Rationale: Speed = 27 * 5/18 = 15/2 m/sec
Total distance covered = 250 + 200 = 450 m
Required time = 450 * 2/15 = 60 sec
The answer: (E)
Question: A train 250 m long is running at a speed of 27 km/hr. In what time will it pass a bridge 200 m long?
Options:
(A) 40
(B) 45
(C) 50
(D) 55
(E) 60