Question 283296: frank can type a report in 4 hours and james takes 7 hours. how long will it take the two of them typing together? Found 2 solutions by richwmiller, oberobic:Answer by richwmiller(17219) (Show Source):
You can put this solution on YOUR website! This problem might make math sense but practically how do you divide up the job of typing a report?
x/4+x/7=1
7x+4x=28
11x=28
x=28/11
x=2 6/11
You can put this solution on YOUR website! Frank works at a rate of 1/4 job per hr.
James works at a rate of 1/7 job per hr.
It takes them 'x' hours to do one entire job.
x*(1/4) + x*(1/7) = 1
.
x/4 + x/7 = 1
.
7x + 4x = 28
.
11x = 28
.
x = 28/11 = 2.54545
.
check by seeing how much of the job each does in 2.54545 hr
2.54545*1/4 = .6363
2.54545*1/7 = .3636
.6363+.3636 = .9999, which is pretty close to 1 whole job
.
Answer:
Working together it takes them 2.54545 hrs.
Or about 2 hr 33 min
.
Done
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