time and work

Question

a man takes 24 days to do a piece of work while woman takes 72 days to do same work . if a contractor engages men and women to do the same work in 4 days .then how many members does the contractor need?

 

(a)9

(b)10

(c)13

(d)16

(e)20

Answer 1

Solve this problem just like your previous problem. You're given the rates of work, so figure out expressions for how much of the work x men could do in 4 days and how much of the work y women could do in 4 days. Then, write an equation using those expressions. You'll want them to complete a total of 1 unit of work (just like 6 houses in your previous question).

 

Finally, test x + y = 9, x + y = 10, etc. to figure out the lowest answer that will give you whole numbers of men and women.