Answers

2016-02-08T20:44:46+05:30
If 8 people take 10 hrs then 4 people will take 20 hrs.
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2016-02-08T20:49:21+05:30
If a wall is built by 8 people in 10 hours and then the no. of people is reduced to half of 8, that is 4 then the time taken by 4 people will be the double of 10 hours, that is 10*2= 20 hours.
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