question: Ravi can do a piece of work in 30 days while Prakash can do it in 40 days. In how many days will they finish it together?
Options:
(A) 17 1/7 days
(B) 17 1/8 days
(C) 17 5/7 days
(D) 17 3/7 days
(E) 13 1/7 days
answer: Stream of consciousness: 1/30 + 1/40 = 7/120
120/7 = 17 1/7 days The answer is (A).
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question: The average of first four prime numbers greater than 10 is?
Options:
(A) 10
(B) 20
(C) 15
(D) 40
(E) 50
answer: Stream of consciousness: 11 + 13 + 17 + 19 = 60/4 = 15 The answer is (C).
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question: In each series, look for the degree and direction of change between the numbers. In other words, do the numbers increase or decrease, and by how much?
Look at this series: 95, 10, 75, 20, 55, ... What number should come next?
Options:
(A) 35
(B) 40
(C) 30
(D) 25
(E) 90
answer: Stream of consciousness: C
30
This is an alternating addition and subtraction series. In the first pattern, 20 is subtracted from each number to arrive at the next. In the second, 10 is added to each number to arrive at the next. The answer is (C).
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question: In how many different ways can the letters of the word "AIM" be rearrangement?
Options:
(A) 4
(B) 2
(C) 7
(D) 9
(E) 6
answer:
Stream of consciousness: Option 'E'
The total number of arrangements is
3P3 = 3! = 6 The answer is (E).
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