P can do work in 12 hr, Q in 6 hr. Together they must do double the work. Time required?
Given:
P = 12 hr Q = 6 hr Work required = double (2 units)
Formula:
Work rate = 1 ÷ time Time = work ÷ combined rate
Solution:
P’s rate = 1/12 Q’s rate = 1/6 = 2/12
Combined = 3/12 = 1/4 Time = 2 ÷ (1/4) = 8 hr
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Two pipes A and B can fill a tank in 28 hours and 21 hours, respectively. If both the pipes are opened simultaneously, then the time taken (in hours) to fill the tank is:
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X alone can complete a work in 56 days and Y alone can do it in 72 days. both completed in:
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8 men and 3 women can do a piece of work in 7 days, whereas 5 men and 1 woman can do it in 12 days. How many men should assist 8 women so that the same work is completed in days?
