question: Which of the following is equal to (y+1)!/y!?
Options:
(A) y-1
(B) 1+(1/y)
(C) 1
(D) y+1
(E) y
answer: Stream of consciousness: (y + 1)! = (y + 1) * x!
(y + 1)!/y! = y + 1 The answer is (D).
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question: The average of fifteen results is 593 and that of the first fourteen is 594. The fifteenth result is?
Options:
(A) 575
(B) 602
(C) 579
(D) 586
(E) 592
answer: Stream of consciousness: 15 * 593 14 * 594 = 579 The answer is (C).
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question: Which of the following is not divisible by 4?
Options:
(A) 10236
(B) 21792
(C) 47816
(D) 91232
(E) 72034
answer: Stream of consciousness: Divisibility rule of 4: Last two digits of the number should be divisible by 4
Option A: 10236, last two digits = 36. Divisible by 4
Option B: 21792, last two digits = 92. Divisible by 4
Option C: 47816, last two digits = 16. Divisible by 4
Option D: 91232, last two digits = 32. Divisible by 4
Option E: 72034, last two digits = 34. Not divisible by 4. Hence 72034 is not divisible by 4 The answer is (E).
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question: Which of the following numbers is divisible by 5?
Options:
(A) 3221
(B) 6175
(C) 6231
(D) 5813
(E) 4251
answer:
Stream of consciousness: 6175. This is the only option with last two digits divisible by 5 The answer is (B).
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