Math: If it takes 5 window washers 7 hours to clean a business building then how long will it take 4?
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Stupid math problems! GAH!
Stupid math problems! GAH!
If it takes 5 window washers 7 hours to clean a business building, then how long will it take only 4 window washers to clean the same business building?
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Tags: Math Problems, Stupid, Window Washers
May 16th, 2009 at 6:41 am
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It takes 35 washer-hours to clean one building. It takes 35/4 washer-hours for 4 washers to do the job.
May 19th, 2009 at 12:39 pm
Small Business Web Hosting
5/7 = 4/x
5x=28
x=5.6 hours
.6 hours =36 minutes so 5 hours, thirty-six minutes
May 21st, 2009 at 7:37 pm
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well, the key here is to get a constant rate:
5/7 = 4/x.
then solve for x: x= 28/5
May 24th, 2009 at 6:54 am
Small Business Web Hosting
its reverse proportion it will take 8.75 hours for 4 of them
just devide 5 by four and multiply by 7
May 26th, 2009 at 3:33 am
Small Business Web Hosting
1 window washer needs (5 *7)= 35 hours
4 window washer need 35/4 = 8 3/4 hours
May 29th, 2009 at 5:23 am
Dolphin Hosting
make a proportion. do 5 over 7. and then 4 over x. then cross mulitply and divide. like this:
5/7 = 4/x
7(4) = 28
28/5= 5.6
5 hours and 40 minutes.
proportions work for almost anything!!
May 29th, 2009 at 1:46 pm
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Create a proportion. Proportions represent a relationship between two numbers. The relationship between the window washers and hours to clean the building is 5/7.
Set this equal to 4/x to determine how many hours it will take 4 windows washers to clean the building. Then cross multiply to solve for x!
5/7 = 4/x
5x = 7 * 4
5x = 28
5x/5 = 28/5
x = 5.6 hours
to convert .6 to minutes:
6/10 of an hour
60 minutes/10 = 6
and 6 * 6 = 36
So the answer is 5 hours and 36 minutes