SOLUTION: Anna can do a work in 12 hrs while Ben can do the same in 8 hrs. Anna has already worked for 90 mins when Ben came, how many more hours will the two finish the remaining work?

Question 658486: Anna can do a work in 12 hrs while Ben can do the same in 8 hrs. Anna has already worked for 90 mins when Ben came, how many more hours will the two finish the remaining work?
Answer by lwsshak3(11628) (Show Source): You can put this solution on YOUR website!
Anna can do a work in 12 hrs while Ben can do the same in 8 hrs. Anna has already worked for 90 mins when Ben came, how many more hours will the two finish the remaining work?
**
let x=time required to finish the job
1/12=Anna's work rate
1/8=Ben's work rate
90 min=1.5 hr
x=hours Ben worked
x+1.5=hours Anna worked
..
x/8+(x+1.5)/12=100% of the job=1
LCD:24
3x+2(x+1.5)=24
3x+2x+3=24
5x=21
x=21/5 hrs
time required to finish the job=21/5 hrs
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