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Question
10 boys can dig a pitch in 12 hours. How long will 8 boys take to do it?
Options
9 h 36 min
15 h
6 h 40 min
13 h 20 min
Solution
15 h
Time is taken by 10 boys to dig a pitch = 12 hours
Time is taken by 1 boy to dig a pitch = 12 × 10 = 120 hours (less boys means more time)
Time is taken by 8 boys to dig a pitch = `120/8` = 15 hours
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