62.A works twice as fast as B. If B can complete a work in 12 days independently, the number of days in which A and B can together finish the work in :
A. 4 days
B. 6 days
C. 8 days
D. 18 days
Answer:
Option : A
Ratio of rates of working of A and B = 2 : 1.
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So, ratio of times taken = 1 : 2.
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∴ A's 1 day's work =
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1
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(2 times of B's work)
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12
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(A + B)'s 1 day's work =
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1
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+
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1
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=
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3
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=
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1
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6
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12
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12
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4
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So, A and B together can finish the work in 4 days.
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