12 man complete a work in 18 days they start but after 6 days four more man join the work. How many days will take all the man to complete the work.

Explanation

12 man complete work in 18 days

1 man complete work in 18*12 days

1 days work `1/(18*12)`

upto 6 days ->12

12 man 1 days work =`1/(18*12)*12=1/18`

12 man, 6 days=`1/18*6=1/3`

Remaining work =2/3

Now, total man=16

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