q: X can finish a work in 21 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) 7
(D) 8
(E) 9
a: Stream of consciousness: Work done by X in 1 day = 1/21
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) / (1/21) = 7 The answer is (C).
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q: The average of first 10 odd numbers is?
Options:
(A) 44
(B) 10
(C) 99
(D) 77
(E) 62
a: Stream of consciousness: Sum of 10 odd no. = 100
Average = 100/10 = 10 The answer is (B).
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q: An design manager has 10patterns of chairs & 6patterns of tables. In how many ways can he make a pair of table & chair?
Options:
(A) 20
(B) 60
(C) 80
(D) 90
(E) 100
a:
Stream of consciousness: He has has ten patterns of chairs and eight patterns of tables
Hence, A chair can be arranged in 10 ways and
A table can be arranged in 6 ways
Hence one chair and one table can be arranged in 10 x 6 ways = 60 ways The answer is (B).
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