Question

16 men can do a work in 20 days, while 14 women can do same work in 30 days. If 40 men starts work and
3 after five days 21 women replaced them, then find time taken by 21 women to complete the remaining
work?
1.5 days
2.12.5 days
3. 7.5 days
4. 15 days
5. 18 days

Answer 1

if 16 men can do the work in 20 days, then the number of days it takes 40 men to complete the work will be x

16 × 20 = 40x

x = 16×20/40 = 8 days

In 8 days they will complete the whole work, so in 5 days they will complete 5/8 of the work.

The rest of the work = 3/8

If 14 women can do the work in 30 days, then 21 women can do the work in y days .

14 ×30 = 21y

y = 14×30/21 = 20

In 20 days 21 women can complete the work, then the time taken by them to complete 3/8 of the work = 3/8 of 20 = 7.5 days