# and another math question

Discussion in 'DAT Discussions' started by ATLATLATL, Apr 18, 2007.

1. ### ATLATLATL 2+ Year Member

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a roof is 45 ft wide and 35 ft long...each shingle covers an area that is 16 in wide and eight inches long...each five gallon pail of tar covers 102 ft of the roof...how many shingles and pails of tar should you purchase to roof the house....

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3. ### Streetwolf Ultra Senior Member Dentist 7+ Year Member

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45 ft = 540 in
35 ft = 420 in

Each shingle is 16 in wide so 540/16 = 33.75 shingles across
Each shingle is 8 in long so 420/8 = 52.5 shingles up

Total shingles = 1771.875 so I guess you'd want 1,772?

Unless they round the # up in each row and column in which case you'd need 34 across and 53 up = 1,802. But they probably want the first answer.

Did you mean 102 square feet? Since there are 45x35 = 1575 square feet of roof, you need 1575/102 = 15.44 five-gallon pails of tar.

4. ### Ex_EE 2+ Year Member

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Wouldn't you need to do 53 x 24 since you can't purchase partial shingles?

5. ### ATLATLATL 2+ Year Member

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yeap that sounds about right thanks so much streetwolf

6. ### ATLATLATL 2+ Year Member

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can someone explain this one to me please....
in a two dimensional coordinate system, point A=(3,-6), point B=(1,1), and point C=(7,6)...find the area of the traingle ABC?

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