Question

if 10 people do a work in 20 days then how much days taken to do this work by 1man

Answer 1

10 people = 20 days
1 people = 20/10 = 2 days.
Hope it helps

Answer 2

If 10 people do a work in 20 days ..
Thus 1 man takes the time to complete that work is 20 × 10 =200 days ...
It's since the number of workers and number of time is indirectly proportional.

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