SOLUTION: Pls. Help me I would like to know the proper solving of this question. Mariko can finish the typing job in 5 hrs. If Monique helps her, they can finish the same job in three hrs

Algebra ->  Rate-of-work-word-problems -> SOLUTION: Pls. Help me I would like to know the proper solving of this question. Mariko can finish the typing job in 5 hrs. If Monique helps her, they can finish the same job in three hrs      Log On


   



Question 205942: Pls. Help me I would like to know the proper solving of this question.
Mariko can finish the typing job in 5 hrs. If Monique helps her, they can finish the same job in three hrs. How long would it take Monique to finish the typing job alone?

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Mariko can finish the typing job in 5 hrs.
If Monique helps her, they can finish the same job in three hrs.
How long would it take Monique to finish the typing job alone?
:
Let x = amt of time required for Monique to do the job alone
:
Let the completed job = 1
;
Each will do a faction of the job, the two fraction add up to 1:
3%2F5 + 3%2Fx = 1
:
Multiply equation by 5x to get rid of the denominator, results:
3x + 3(5) = 5x
:
15 = 5x - 3x
:
15 = 2x
x = 15%2F2
x = 7.5 hrs working alone
:
:
Is this true:
3%2F5 + 3%2F7.5 =
.6 + .4 = 1