SOLUTION: It takes 20 workers a total of 30 days to pave a highway. How many days would it take 15 workers to do the same job?

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Question 967600: It takes 20 workers a total of 30 days to pave a highway. How many days would it take 15 workers to do the same job?
Found 2 solutions by josgarithmetic, askhari139:
Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
"pave a highway" and "the same job", each is ONE job.

For a rate r, of one worker in JOBS per DAY, any number n of workers working at the same time on the job make the rate nr.

20r%2A30=1=15r%2At, using t for the number of days.
Observe that this follows uniform rate relationship for doing work,
RT=J rate time job-quantity.

Answer by askhari139(3) About Me  (Show Source):
You can put this solution on YOUR website!
Assuming that all the workers are equally efficient, i.e., they each one takes the same amount of time to do a given amount of work,
Time taken by 20 workers to finish the job(T20) = 30 days
Time taken by one worker to finish the job(T1) = T20*30 days = 600 days
Time taken by 15 workers to finish the job(T15) = T1/15 = 40 days