Come on, think about it.
If 2 of us can paint a house in 4 days, how long would it take to paint it
by yourself?
What operation did you perform?
Did you notice that 28 is half of 56?
(still trying to visualize that fraction of a man working)
9 men do a piece of work in 28 days. How many men will do it in 56 days?
2 answers
Well... 28 is Half of 56. 56 is a longer period than 28 days. 9 men can complete it in 28. If it will take longer for the completion, there should be more people completing the work.
Therefore, since 28 is half of 56;
9 men will do it in 28 days and
18 men in 56 days
Therefore, since 28 is half of 56;
9 men will do it in 28 days and
18 men in 56 days