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During a special promotion, a certain filling station is offering a 10 [#permalink]
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20 Feb 2015, 03:04
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61% (02:09) correct 39% (02:19) wrong based on 223 sessions
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During a special promotion, a certain filling station is offering a 10 percent discount on gas purchased after the first 10 gallons. If Kim purchased 20 gallons of gas, and Isabella purchased 25 gallons of gas, then Isabella‟s total pergallon discount is what percent of Kim‟s total pergallon discount? (A) 80% (B) 100% (C) 116.7% (D) 120% (E) 140%
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Re: During a special promotion, a certain filling station is offering a 10 [#permalink]
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20 Feb 2015, 04:01



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During a special promotion, a certain filling station is offering a 10 [#permalink]
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20 Feb 2015, 22:48
Stardust Chris wrote: During a special promotion, a certain filling station is offering a 10 percent discount on gas purchased after the first 10 gallons. If Kim purchased 20 gallons of gas, and Isabella purchased 25 gallons of gas, then Isabella‟s total pergallon discount is what percent of Kim‟s total pergallon discount?
(A) 80%
(B) 100%
(C) 116.7%
(D) 120%
(E) 140% hi, just take the discount to be 1 unit on every gallon above 10.. kim saved 10 on 20 gallons or\(\frac{1}{2}\)per gallon... isabella saved 15 on 25 gallons or \(\frac{15}{25}=\frac{3}{5}\)per gallon.. %=\(100*(\frac{3}{5})/(\frac{1}{2})=\frac{600}{5}=120%\)...ans B
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Re: During a special promotion, a certain filling station is offering a 10 [#permalink]
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15 Apr 2016, 02:35
Hi Bunuel, Thanks for the explanation. A small clarification required though.. You have applied the specified discount on #Units of Gallons. Though it doesn't matter but I chose to look at the given discount in terms of Price/Gallon ($1/G) and then followed the same approach. I usually take time on percent questions if they're of 700+ level. Do you see any obvious flaw in my approach? I could work on some particular concept files if you think that may help me provide a direct and efficient approach to percent problems. Accuracy is moderate on higher level percent question but time is of concern. This includes my accuracy on Manhattan CATS. Hari Bunuel wrote: Stardust Chris wrote: During a special promotion, a certain filling station is offering a 10 percent discount on gas purchased after the first 10 gallons. If Kim purchased 20 gallons of gas, and Isabella purchased 25 gallons of gas, then Isabella‟s total pergallon discount is what percent of Kim‟s total pergallon discount?
(A) 80%
(B) 100%
(C) 116.7%
(D) 120%
(E) 140% Kim purchased 20 gallons of gas. She paid for 10 + 0.9*10 = 19 gallons, so the overall discount she got was 1/20 = 5%. Isabella purchased 25 gallons of gas. She paid for 10 + 0.9*15 = 23.5 gallons, so the overall discount she got was 1.5/25 = 6%. 6 is 6/5*100 = 120% of 5. Answer: D. Posted from my mobile device



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During a special promotion, a certain filling station is offering a 10 [#permalink]
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08 Mar 2017, 10:19
During a special promotion, a certain filling station is offering a 10 percent discount on gas purchased after the first 10 gallons. If Kim purchased 20 gallons of gas, and Isabella purchased 25 gallons of gas, then Isabella’s total pergallon discount is what percent of Kim’s total pergallon discount? (A) 80% (B) 100% (C) 116.7% (D) 120% (E) 140%
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08 Mar 2017, 10:32



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Re: During a special promotion, a certain filling station is offering a 10 [#permalink]
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23 Aug 2017, 03:37
Stardust Chris wrote: During a special promotion, a certain filling station is offering a 10 percent discount on gas purchased after the first 10 gallons. If Kim purchased 20 gallons of gas, and Isabella purchased 25 gallons of gas, then Isabella‟s total pergallon discount is what percent of Kim‟s total pergallon discount?
(A) 80%
(B) 100%
(C) 116.7%
(D) 120%
(E) 140% Let R be the fixed rate of the gas per gallon. So for first 10 gallon, rate = 10 R After this the gas will be available at 10 percent discount. Kim purchased 20 gallon of gas. So, price = 10R +.9*10 R = 19R Discount per gallon = 1/20 Isabella purchased 25 gallons of gas. So, price = 10 R + .9*15 R = 22.5 R Discount per gallon = 1.5/25 = 3/50 So, percentage of Isabella‟s total pergallon discount w.r.t Kim‟s total pergallon discount = (3/50)/(1/20) *100 = 120% Answer D
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Re: During a special promotion, a certain filling station is offering a 10 [#permalink]
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25 Aug 2017, 11:07
Stardust Chris wrote: During a special promotion, a certain filling station is offering a 10 percent discount on gas purchased after the first 10 gallons. If Kim purchased 20 gallons of gas, and Isabella purchased 25 gallons of gas, then Isabella‟s total pergallon discount is what percent of Kim‟s total pergallon discount?
(A) 80%
(B) 100%
(C) 116.7%
(D) 120%
(E) 140% Let’s assume that the price per gallon of gas is $10. Thus, the discounted price per gallon of gas after the first 10 gallons is 0.9 x 10 = $9. In other words, after the first 10 gallons, each additional gallon has a $1 discount in price. Now let’s calculate the total discount for each person. Since Kim purchased 20 gallons of gas, the 10 additional gallons (that is, after the initial 10 gallons) will receive a $10 discount, so her total pergallon discount is 10/20 = $0.50. Since Isabella purchased 25 gallons of gas, the 15 additional gallons (that is, after the initial 10 gallons) will receive a $15 discount, so her total pergallon discount is 15/25 = $0.60. Therefore, Isabella’s total pergallon discount is 0.60/0.50 = 6/5 = 1.2 = 120% of Kim’s total pergallon discount. Answer: D
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During a special promotion, a certain filling station is offering a 10 [#permalink]
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26 Aug 2017, 09:16
shashankism wrote: Stardust Chris wrote: During a special promotion, a certain filling station is offering a 10 percent discount on gas purchased after the first 10 gallons. If Kim purchased 20 gallons of gas, and Isabella purchased 25 gallons of gas, then Isabella‟s total pergallon discount is what percent of Kim‟s total pergallon discount?
(A) 80%
(B) 100%
(C) 116.7%
(D) 120%
(E) 140% Let R be the fixed rate of the gas per gallon. So for first 10 gallon, rate = 10 R After this the gas will be available at 10 percent discount. Kim purchased 20 gallon of gas. So, price = 10R +.9*10 R = 19R Discount per gallon = 1/20 Isabella purchased 25 gallons of gas. So, price = 10 R + .9*15 R = 22.5 RDiscount per gallon = 1.5/25 = 3/50 So, percentage of Isabella‟s total pergallon discount w.r.t Kim‟s total pergallon discount = (3/50)/(1/20) *100 = 120% Answer DI think you made a typo error in the highlighted portion, It should be 23.5 R



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During a special promotion, a certain filling station is offering a 10 [#permalink]
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07 Sep 2017, 20:50
Let the cost of fuel be $10 per gallon. Kim First, 10 gallons price=10*$10=$100 2nd 10 gallon Price=10*$9=90 (Discount of 10% or $1 after first 10 gallons) Total Paid $190 In case there would have been no discount than amount paid would have been $200(20*10) Savings $10. Total savings on Total fuel purchased=\(\frac{10}{20}\)=\(\frac{1}{2}\) Isabella First 10 gallon price=10*$10=100 2nd 15 gallon Price=15*$9=135 (Discount of 10% or $1 after first 10 gallons) Total Paid $235 In case there would have been no discount than amount paid would have been $250(25*$10) Savings $15. Total savings on Total fuel purchased=\(\frac{15}{25}\)=\(\frac{3}{5}\)
% of \(\frac{Isabella}{Kim}\)= \(\frac{3}{5}\)÷\(\frac{1}{2}\)=\(\frac{6}{5}\)=1.2*100=120%




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