SOLUTION: Jerry can assemble a computer by himself in 45 minutes. Working with an assistant, he can assemble a computer in 40 minutes. How long would it take his assistant to do it working a

Algebra ->  Rational-functions -> SOLUTION: Jerry can assemble a computer by himself in 45 minutes. Working with an assistant, he can assemble a computer in 40 minutes. How long would it take his assistant to do it working a      Log On


   

Question 1103030: Jerry can assemble a computer by himself in 45 minutes. Working with an assistant, he can assemble a computer in 40 minutes. How long would it take his assistant to do it working alone?
Found 2 solutions by Fombitz, jorel1380:
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Rate x Time = Output
.
.
.
R%5BJ%5D%2A45=1
R%5BJ%5D=1%2F45
.
.
%28R%5BJ%5D%2BR%5BA%5D%29%2A40=1
R%5BJ%5D%2BR%5BA%5D=1%2F40
Substituting from above,
1%2F45%2BR%5BA%5D=1%2F40
R%5BA%5D=1%2F40-1%2F45
R%5BA%5D=9%2F360-8%2F360
R%5BA%5D=1%2F360
So,
R%5BA%5D%2At%5BA%5D=1
t%5BA%5D=1%2FR%5BA%5D
t%5BA%5D=360
360 minutes or 6 hours

Answer by jorel1380(3719) About Me  (Show Source):
You can put this solution on YOUR website!
Jerry assembles 1/45 a computer per minute. Together with an assistant, they assemble 1/40th a computer per minute. Then, for the assistant alone:
1/40-1/45=9/360-8/360=1/360
1/(1/360)=360
It would take the assistant 360 minutes, working alone, to assemble a computer
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