[Ans] (A)
[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
[CoT] 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.

[Ans] (B)
[Question] In g is a positive integer smaller than 200 and (14g)/60 is an integer, then g has how many different positive prime factors?
Options:
(A) 2
(B) 3
(C) 5
(D) 6
(E) 8
[CoT] 7g/30 tells us that g is a factor of 30, which has 2, 3, and 5 as its prime factors. Each of them is distinct. Moreover, all multiples of 30 less than 200 can be derived by multiplying these prime factors alone. Thus, number of different prime factors is 3.

[Ans] (C)
[Question]
A train 150 m long running at 72 kmph crosses a platform in 25 sec. What is the length of the platform?
Options:
(A) 338
(B) 277
(C) 350
(D) 881
(E) 271
[CoT] D = 72 * 5/18 = 25 = 500 150 = 350