Question 52276: This is a word problem and I am stumped on this. It was given on a test and I have to correct it by this evening 9/14/06 to get a grade. Can you help?
Here is the word problem:
An electrician can wire a house in 20 hours. If she works with an apprentice, the same job can be completed in 15 hours. How long would it take the apprentice, working alone, to wire the house?
The teacher's answer is 60/7
That is not what I got. This is what I did.
x/20 +x/15 = 1
300/1 (x/20 + x/15 = 1)
15x + 20x = 35
35x/35 = 300/35
When I divide 35 into 300 I come up with 8.57 and can not figure out how she got 60/7.
Answer by funmath(2933)   (Show Source):
You can put this solution on YOUR website! Your answer is the same as hers, I'm not sure about some of what you did to get there, but 300/35=60/7 when you reduce it.
The numerator reduces this way 300 divided by 5 is 60.
The denominator reduces this way 35 divided by 5 is 7.
Try comparing the decimal 8.57 that you got, by putting her fraction into the calculator and you will get 8.57.
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