Question

If 7 boys can complete a job in 21 days, how long will 21 boys take to complete the job?
pls ans fast
show working also​

Answer 1

Answer:

9days

Step-by-step explanation:

Since 3 men or 9 boys do the work in 21 days, 1 man is equivalent to 3 boys.

The work involved is 9*21 equivalent to 189 boy-days.

So 5 men and 6 boys is the same as 15+6 = 21 boys. So the time taken is 189 boy-days/21 boys = 9 days.