Arithmetic Ability
Time and Work

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Q.

Relation Between Efficiency and Time A is twice as good a workman as B and is therefore able to finish a piece of work in 30 days less than B.In how many days they can complee the whole work; working together?

View Answer

Correct choice: C

Explanation:

Ratio of times taken by A and B = 1 : 2. The time difference is (2 - 1) 1 day while B take 2 days and A takes 1 day. If difference of time is 1 day, B takes 2 days. If difference of time is 30 days, B takes 2 x 30 = 60 days. So, A takes 30 days to do the work. A's 1 day's work = 1/30 B's 1 day's work = 1/60 (A + B)'s 1 day's work = 1/30 + 1/60 = 1/20 A and B together can do the work in 20 days.
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