Rationale: 3!4! Required probability = 3!4!/6! = 1/5
The answer: (A)
Question: If six persons sit in a row, then the probability that three particular persons are always together is -.
Options:
(A) 1/5
(B) 1/7
(C) 1/9
(D) 1/2
(E) 2/7
Reasoning: Final number = Initial number + 50%(original number) = 60 + 50%(60) = 60 + 30 = 90.
Ans: (C)
Question: 60 is increased by 50%. Find the final number.
Options:
(A) 100
(B) 110
(C) 90
(D) 30
(E) 160
Rationale: I = (500*9*6)/100 = 270
The answer: (B)
Question: Find the simple interest on Rs.500 for 9 months at 6 paisa per month?
Options:
(A) 287
(B) 270
(C) 276
(D) 129
(E) 211
Reasoning: Simple interest = (18000 * 4 * 15)/100 = Rs. 10800
Amount = P + I = 18000 + 10800 = Rs. 28800
Ans: (D)
Question: What amount does Kiran get if he invests Rs. 18000 at 15% p.a. simple interest for four years?
Options:
(A) 22777
(B) 28877
(C) 26888
(D) 28800
(E) 67881
Rationale: A + B = 1/20 + 1/15 = 7/60
A + C = 1/20 + 1/12 = 8/60
7/60 + 8/60 = 15/60 = 1/4
4 days * 2 = 8 days
The answer: (B)
Question: A can do a piece of work in 20 days. B in 15 days A and C in 12 days. In how many days can A finish the work if he is assisted by B on one day and C on the next, alternately?
Options:
(A) 7 days
(B) 8 days
(C) 5 days
(D) 4 days
(E) 2 days
Rationale: Answer = B = 1
20 - 19 = 30-29 = 40-39 = 50-49 = 1
The answer: (B)
Question: If X and Y are both positive two-digit integers and share no digits, and X > Y, what is the smallest possible value of X - Y?
Options:
(A) 0
(B) 1
(C) 2
(D) 3
(E) 9