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If 72% of rectangular floor is covered by a rectangular rug that is 9
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30 Aug 2018, 05:13
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If 72% of rectangular floor is covered by a rectangular rug that is 9
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30 Aug 2018, 05:45
Bunuel wrote: If 72% of rectangular floor is covered by a rectangular rug that is 9 feet by 16 feet, what is the area, in square feet, of the uncovered floor?
A. 28 B. 56 C. 80 D. 200 E. 560 Hi .. 72% of total =9*16 Don't multiply, may save time while dividing..So \(\frac{72}{100}*total=9*16.......total =9*16*\frac{100}{72}\) Divide both by 9 first.. \(total = 16*\frac{100}{8}\) Now divide by 8 \(total=2*100=200\) Therefore uncovered area = 2009*16=56 B
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If 72% of rectangular floor is covered by a rectangular rug that is 9
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Updated on: 30 Aug 2018, 06:05
Bunuel wrote: If 72% of rectangular floor is covered by a rectangular rug that is 9 feet by 16 feet, what is the area, in square feet, of the uncovered floor?
A. 28 B. 56 C. 80 D. 200 E. 560 Let the total area be x we are given 0.72(x)=16*9 =>x=200 Area of uncovered floor is 28% of x = 56 Option B is the Answer.
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Originally posted by gmat1393 on 30 Aug 2018, 05:51.
Last edited by gmat1393 on 30 Aug 2018, 06:05, edited 1 time in total.



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If 72% of rectangular floor is covered by a rectangular rug that is 9
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30 Aug 2018, 05:56
Isn't the area of uncovered floor 28 percemt of 200?
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Re: If 72% of rectangular floor is covered by a rectangular rug that is 9
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30 Aug 2018, 05:57
chetan2u wrote: Bunuel wrote: If 72% of rectangular floor is covered by a rectangular rug that is 9 feet by 16 feet, what is the area, in square feet, of the uncovered floor?
A. 28 B. 56 C. 80 D. 200 E. 560 Hi .. 72% of total =9*16 Don't multiply, may save time while dividing..So \(\frac{72}{100}*total=9*16.......total =9*16*\frac{100}{72}\) Divide both by 9 first.. \(total = 16*\frac{100}{8}\) Now divide by 8 \(total=2*100=200\) D Shouldn't the ans be 0.28 x 200?as it asks for uncovered area Posted from my mobile device



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Re: If 72% of rectangular floor is covered by a rectangular rug that is 9
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30 Aug 2018, 06:04
chetan2u wrote: Bunuel wrote: If 72% of rectangular floor is covered by a rectangular rug that is 9 feet by 16 feet, what is the area, in square feet, of the uncovered floor?
A. 28 B. 56 C. 80 D. 200 E. 560 Hi .. 72% of total =9*16 Don't multiply, may save time while dividing..So \(\frac{72}{100}*total=9*16.......total =9*16*\frac{100}{72}\) Divide both by 9 first.. \(total = 16*\frac{100}{8}\) Now divide by 8 \(total=2*100=200\) D Hi chetan2uHere is my approach. % of floor ___Area 72 > 9*16 28 > \(\frac{(9*16)*28}{72}\) > Area of uncovered floor = \(\frac{(9*16)*28}{72}=\frac{(9*16)*28}{9*8}=2*28=56\) > Answer B. According to your solution, shouldn't 200 be the area of total floor, not the area of uncovered floor ? Please correct me if I am wrong. Thank you.
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Re: If 72% of rectangular floor is covered by a rectangular rug that is 9
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30 Aug 2018, 06:07
Izzyjolly wrote: chetan2u wrote: Bunuel wrote: If 72% of rectangular floor is covered by a rectangular rug that is 9 feet by 16 feet, what is the area, in square feet, of the uncovered floor?
A. 28 B. 56 C. 80 D. 200 E. 560 Hi .. 72% of total =9*16 Don't multiply, may save time while dividing..So \(\frac{72}{100}*total=9*16.......total =9*16*\frac{100}{72}\) Divide both by 9 first.. \(total = 16*\frac{100}{8}\) Now divide by 8 \(total=2*100=200\) D Hi chetan2uHere is my approach. % of floor ___Area 72 > 9*16 28 > \(\frac{(9*16)*28}{72}\) > Area of uncovered floor = \(\frac{(9*16)*28}{72}=\frac{(9*16)*28}{9*8}=2*28=56\) > Answer B. According to your solution, shouldn't 200 be the area of total floor, not the area of uncovered floor ? Please correct me if I am wrong. Thank you. You are absolutely correct .. I have answered for the total area, but it has to be for uncovered..
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Re: If 72% of rectangular floor is covered by a rectangular rug that is 9
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30 Aug 2018, 06:13
Bunuel wrote: If 72% of rectangular floor is covered by a rectangular rug that is 9 feet by 16 feet, what is the area, in square feet, of the uncovered floor?
A. 28 B. 56 C. 80 D. 200 E. 560 Here 72% = 16*9 = 144 Therefore, uncovered floor = 28% Now, since 72% = 144 Therefore, 28% = (144/72)*28 = 56 Hence B is the answer.



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If 72% of rectangular floor is covered by a rectangular rug that is 9
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30 Aug 2018, 06:31
Bunuel wrote: If 72% of rectangular floor is covered by a rectangular rug that is 9 feet by 16 feet, what is the area, in square feet, of the uncovered floor?
A. 28 B. 56 C. 80 D. 200 E. 560 Note: we are looking for the are of the Uncovered Floor. Covered is 72% . So uncovered area is 28%.
covered floor = 16*9 = 144.
72% represents 144
1% represents 144/72
28% represents 144*28 / 72
= 56.
The best answer is B.



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Re: If 72% of rectangular floor is covered by a rectangular rug that is 9
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30 Aug 2018, 07:15
Bunuel wrote: If 72% of rectangular floor is covered by a rectangular rug that is 9 feet by 16 feet, what is the area, in square feet, of the uncovered floor?
A. 28 B. 56 C. 80 D. 200 E. 560 \(\frac{16*9}{72}*28\) = 56, Answer must be (B)PS : Skippe steps in between , anyone requirng explainations please feel free to revert.
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Re: If 72% of rectangular floor is covered by a rectangular rug that is 9
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04 Sep 2018, 04:38
Bunuel wrote: If 72% of rectangular floor is covered by a rectangular rug that is 9 feet by 16 feet, what is the area, in square feet, of the uncovered floor?
A. 28 B. 56 C. 80 D. 200 E. 560 Letting n = the area of the floor, we can create the following equation: (9 x 16) = 0.72n 144 = 0.72n 200 = n So the area of the uncovered floor is 200  144 = 56 square feet. Answer: B
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