maths --plse help me..

posted by .

if 16 men can build a road of 9 km in 3 days then how many men can build 21 km road in 5 days.

• maths --plse help me.. -

we have

9km/(16men*3days) = 3/16 km/man-day
so, you conversion factor is

16/3 man-day/km

so, with 21km and 5 days, you will need

16/3 man-day/km * 21km / 5day = 22.4 men

Similar Questions

1. maths

300 men were engaged to complete a job in a certain number of days. but due to another assignment fifteen men dropped the second day, fifteen more men dropped the third days and so on .if takes fifteen more days to finish the work …
2. STATISTICS

Length of Hospital Stays: The average length of “short” hospital stays for men is slightly longer thatn that for women: 5.2 days vs. 4.5 days. A random sample of recent hospital stays for both men and women revealed the following. …
3. math

9 men build a house in a working 4 days .how many workmen ,working at the same rate willbe needed to build a house in 3 days
4. math

20 men can do a piece of work in 24 days. After working for 6 days, additional men are employed to finish the work in 21 days from the beginning. Find the number of additional men
5. math

A construction crew has just finished building a road. The road is 10 kilometers long. If the crew worked for 4 2/3 days, how many kilometers of road did they build each day?
6. Maths ( urgent help )

20 men can do a piece of work in 24 days. After working for 6 days, an additional number of men are taken to finish the work in 21 days from the beginning. Find the number of additional men . . . I tried using variation method but …
7. Maths

A soak away was dug by 5 men in 24 days. How many days will it take 15 men to dig it if they were to work at the same rate.
8. Math

It takes 8 men to build a fence in 9 days so how long it would take 3 men to build the same fence?
9. maths

If it takes 10 men to build a house in 6 months how many men would be needed to build it in 4 months
10. math

24 men works for 14 days, 2 days after they started working, 4 more men joined them and after 2 more days, 6 men left. How many more days will they now take to complete the remaining work?

More Similar Questions