Answer

First data: 45 men complete a work in 16 days.

Second data: 6 days after they started working 30 more men joined them.

Final question: how many days they will need to complete to finish remaining work?

mens * days = total work

45 *16=720

One man do work in one day=1/720

45 men’s one day work(within 6 days) 1/16

Within 6 days they complete job=days*one day work=6*1/16=6/16=3/8

Remaining job=1-3/8=5/8

See the time and work formula

75 men do work in single day=total no of man/(total work)=75/720=5/48

Days * per day work = total work

X*5/48=5/8

X==(5/8*48/5)=6 days

They will need 6 days to complete reaming work Reference form R.S Aggarwal Book