Question 750288: A student must leave for campus in 10 minutes or he will be late for class. Unfortunately, he is snowed in. He can shovel the driveway in 16 minutes, and his brother claims to be able to do it in 14 minutes. If they shovel together, how long will it take to clear the driveway? Will this give enough time for the student to get to the campus?
It will take about ____ minutes to clear the driveway together.
Will this give the student enough time to get to the campus?
I tried to solve this and came up with the wrong answer and am hoping I can find out where I am wrong. It will take about __x__ minutes to clear the driveway together. So, 1/x =1/14+1/16 x = 7.47
So It will take about __7.47__ minutes to clear the driveway together. I also tried 8 and it was also wrong, thank you!
This will give the student enough time to get to the campus
Answer by ankor@dixie-net.com(22740)   (Show Source):
You can put this solution on YOUR website! A student must leave for campus in 10 minutes or he will be late for class.
Unfortunately, he is snowed in.
He can shovel the driveway in 16 minutes, and his brother claims to be able to do it in 14 minutes.
If they shovel together, how long will it take to clear the driveway?
Will this give enough time for the student to get to the campus?
:
Use a shared work equation, let t = time working together
Let the completed job = 1 (a cleared driveway)
:
 +  = 1
multiply equation by the least common multiple of 16 and 14, that 112, results:
7t + 8t = 112
15t = 112
t = 112/15
t = 7.47 minutes, so you are right!
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