Question

If 20 persons can dig a tank of 20 metres long, 10 metres wide
and 8 metres deep in 27 days by working 8 hours per day, in how many days of 9
hours, 60 persons can dig 2 tank of 60 metres long, 20 metres wide and 10 metres
deep?​

Answer 1

Answer:

This answer is photo below.