question:A man, a woman and a boy can complete a job in 3, 4 and 12 days respectively. How many boys must assist 1 man and 1 woman to complete the job in 1/4 of a day?
Options:
(A) 41
(B) 43
(C) 31
(D) 84
(E) 81
answer:(A)
Stream of consciousness:(1 man + 1 woman)'s 1 day work = 1/3 + 1/4 = 7/12
Work done by 1 man and 1 women in 1/4 day = ((7/12) x (1/4)) = 7/48
Remaining work = 1 - 7/48 = 41/48
Work done by 1 boy in 1/4 day = ((1/12) x (1/4)) = 1/48
Therefore, Number of boys required = ((41/48) x 48) = 41

question:A no.when divided by 225 gives a remainder 43, what remainder will beobtained by dividingthe same no.17?
Options:
(A) 2
(B) 7
(C) 9
(D) 11
(E) 13
answer:(E)
Stream of consciousness:225 + 43 = 268/17 = 13 (Remainder)

question:A telephone company needs to create a set of 3-digit area codes. The company is entitled to use only digits 2, 4 and 3, which can be repeated. If the product of the digits in the area code must be even, how many different codes can be created?
Options:
(A) 20
(B) 26
(C) 24
(D) 22
(E) 30
answer:
(B)
Stream of consciousness:Total # of codes possible is 3*3*3 = 27. Oit of those 27 codes only the product of 333 will be odd, the remaining 26 will have either 2 or 4 in them, which ensures that their product will be even. Therefore the number of codes where the product of the digits is even = (total) - (restriction) = 27 - 1 = 26.