Question: Out of 7 consonants and 4 vowels, how many words of 3 consonants and 2 vowels can be formed?
Options:
(A) 25200
(B) 2543
(C) 2344
(D) 233445
(E) 52757
Answer: Number of ways of selecting (3 consonants out of 7) and (2 vowels out of 4) = (7C3 x 4C2) = ( 7 x 6 x 5 x 4 x 3 ) 3 x 2 x 1 2 x 1 = 210. Number of groups, each having 3 consonants and 2 vowels = 210. Each group contains 5 letters. Number of ways of arranging 5 letters among themselves = 5! = 5 x 4 x 3 x 2 x 1 = 120. Required number of ways = (210 x 120) = 25200.
The answer is (A).

Question: Express 50 mps in kmph?
Options:
(A) 172
(B) 160
(C) 150
(D) 180
(E) 120
Answer: 25 * 18/5 = 180 kmph
The answer is (D).

Question: Find the least number must be subtracted from 427398 so that remaining no.is divisible by 15?
Options:
(A) 2
(B) 3
(C) 5
(D) 7
(E) 8
Answer: On dividing 427398 by 15 we get the remainder 3, so 3 should be subtracted
The answer is (B).

Question: X can finish a work in 18 days. Y can finish the same work in 15 days. Yworked for 10 days and left the job. how many days does X alone need to finish the remaining work?
Options:
(A) 3
(B) 5
(C) 6
(D) 7
(E) 9
Answer:
Work done by X in 1 day = 1/18
Work done by Y in 1 day = 1/15
Work done by Y in 10 days = 10/15 = 2/3
Remaining work = 1 2/3 = 1/3
Number of days in which X can finish the remaining work = (1/3) / (1/18) = 6
The answer is (C).