Question
‘A’ alone can complete a work in 50 hours. ‘A’
started the work alone and left after working on it for 20 hours. If ‘B’ completed the rest of the work in 10 hours then find the time taken by ‘A’ and ‘B’ together to complete the whole work.Solution
Let the total work = 200 units Then, efficiency of ‘A’ = (200/50) = 4 units/hour Work completed by ‘A’ alone in 20 hours = 4 × 20 = 80 units Remaining work = 200 – 80 = 120 units So, efficiency of ‘B’ = 120/10 = 12 units/hour Therefore, combined efficiency of ‘A’ and ‘B’ = 12 + 4 = 16 units/hour So, time taken by ‘A’ and ‘B’ together to complete the work = (200/16) = 12.5 hours
Select the number from among the given option that can replace the question mark (?) in the following series.
11, 18, 30, 52, 94, ?
Select the number from among the given option that can replace the question mark (?) in the following series.
6, 31, 126, 381, 766, ?
M/14 : O/12 : : U/6 : ?
Select the related word/letters/number from the given alternatives.
LHX: OEA : : PFT : ?
Find the missing term in the following series:
43 44 ? 69 185
...Find the missing numbers.
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What will come in the place of question mark?
In each of the following questions, select the related number from the given alternatives:
8/15 : 2/5 : : 16/21 : ?
Find the missing term in the given series:
4      3.5      ?           22.875               ...
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