This is known as a "see-saw" problem.....that is, the product of one side of the equation must equal the product of the other side
So, two people dig a hole in 5 hrs. = 300 minutes
So
2 x 300 = N * 5 where N is the number of people we're looking for
600 = N * 5 divide by 5
120 = N
So it takes 120 people to dig the same hole in 5 minutes
To see the logic of this, we need to dig the hole 60 times as fast......therefore....we need 60 times as many people.... and 60 x 2 = 120.....!!!
