Question 168501:  painting if 50 feet by 30ft they want to put a border to be 25% of the painting what is the exact width of the border? 
 Answer by stanbon(75887)      (Show Source): 
You can  put this solution on YOUR website! painting of 50 feet by 30ft they want to put a border to be 25% of the painting what is the exact width of the border? 
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If I read you correctly the area of the border is to be 25% of the area 
of the painting. 
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The area of the painting is 50x30 = 1500 sq ft 
25% of 1500 = 375 sq. ft. 
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Assume the width of the border is x ft. 
At this point you should sketch an appropriate figure of the painting with 
its border. 
The width of the border is 50+2x ft. 
The length of the border is 30+2x ft. 
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So, the area of the picture INCLUDING its border is (50+2x)(30+2x) sq. ft. 
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EQUATION: 
Entire area - picture area = 375 sq ft 
(50+2x)(30+2x) - 1500 = 375 
1500 + 160x + 4x^2 = 375 
4x^2 + 160x = 1125 
4x^2 + 160x - 1125 = 0 
x=6.1007663... ft 
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Cheers, 
Stan H. 
 
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