Question 476072
If 12 men can dig 35 holes in 14 days,
(a) how many men are needed to dig 35 holes in 8 days,
35 holes takes 168 man-days
168 man-days/8 days = 21 men
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(b) how many days would it take 12 men to dig 30 holes?
35 holes takes 168 man-days
--? 168/35 man-days per hole
= 4.8 man-days per hole
4.8*30 = 144 man-days
144 man-days/12 men = 12 days
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Keeping the units with the calculations makes it more obvious.