SOLUTION: peter and paul can do a certain job in 3 hours. on a given day, they worked together for 1 hour then paul left and peter finishes the rest of the work in 8 more hours? how long wil
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-> SOLUTION: peter and paul can do a certain job in 3 hours. on a given day, they worked together for 1 hour then paul left and peter finishes the rest of the work in 8 more hours? how long wil
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Question 746799: peter and paul can do a certain job in 3 hours. on a given day, they worked together for 1 hour then paul left and peter finishes the rest of the work in 8 more hours? how long will it take peter to do the job alone? Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! peter and Paul can do a certain job in 3 hours.
let x = Pete's time working alone
let y = Paul's time
let the completed job = 1
:
A shared work equation + = 1
:
on a given day, they worked together for 1 hour then Paul left and peter finishes the rest of the work in 8 more hours?
Then Pete works 9 hrs. + = 1
:
We can use elimination here, multiply above equation by 3
Subtract the 1st equation + = 3 + = 1
--------------Subtraction eliminates y, find x = 2
2x = 24
x = 12 hrs for Peter to do the job alone?
:
:
See if that checks out, find y: + = 1 + = 1
y = 4
Check in the 2nd equation + = 1; confirms our solutions of x = 12 & y = 4
