# maths

posted by .

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 now.find the number of days in which the work was completed. please hellllllppppp.

• maths -

The number of man-hours that were used were

300 + 285 + 270 + 255 + ... + 15 + 0
Since we can't count the + 0 , (nobody worked that day) ,
we need the number of terms of
300+285 + ... + 15

the left side is an AS where a = 300 , d = -15 , n = ?

when the last term is 15
15 = a + d(n-1)
15 = 300 - 15(n-1)
15 = 300-15m + 15
15n = 300
n = 20

• maths -

Reiny's solution just tells us the max number of days not how many days were actually used.
We know that 15 more days were used than originally planned with the full 300.

300d= the sum of the progression

## Respond to this Question

 First Name School Subject Your Answer

## Similar Questions

1. ### maths, proportion

twelve men take 6 hours to finish a piece of work. after the 12 men have worked for 1 hour, the contractor decides to call in 8 more men to complete the remaining work. how many more hours would the 20 men take to complete the remaining …
2. ### airthmetic progression

300 men wre engaged to complete a job in acertain number of days.but due to another assignment 15 men dropped the second day,15 more dropped in the third day and so on. it takes 15 more days to finish the work now.find the no. of days …
3. ### math

if 8 men can do a job in days, what is the percentage increase in number of days required to do the job when 2 men are released?
4. ### math

I 64 men do a job in 15 days how many more men are needed to do the job in 12 dsys?
5. ### math

If a job takes 64 men to complete in 15 days, how many more men will take to complete the job in 12 days?
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

300 mens were engaged to complete a job in a certain number of days. but due to another assignment 15 men dropped the 2nd day, 15 more men dropped the 3rd day and so on.it takes 15 more days to finish the work now. find the number …
8. ### math

If a job can be done by 10 workers in 5 hours, the work load is 10(5) = 50 man-hours. If 4 workers is doing the job for 6 hours, the work done is 4(6) = 24 man-hours. A remaining of 50 - 24 = 26 man-hours of work still needs to be …
9. ### Maths

64 men can complete a work in 15 days.to complete the same work in 12 days how many more men are required
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