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A paint mixture was formed by mixing exactly 3 colors of paint. By vol
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26 Apr 2019, 03:18
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A paint mixture was formed by mixing exactly 3 colors of paint. By volume, the mixture was x% blue paint, y% green paint, and z% red paint. If exactly 1 gallon of blue paint and 3 gallons of red paint were used, how many gallons of green paint were used? (1) x = y (2) z = 60 DS24751.01 OG2020 NEW QUESTION
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Re: A paint mixture was formed by mixing exactly 3 colors of paint. By vol
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26 Apr 2019, 04:42
A paint mixture was formed by mixing exactly 3 colors of paint. By volume, the mixture was x% blue paint, y% green paint, and z% red paint. If exactly 1 gallon of blue paint and 3 gallons of red paint were used, how many gallons of green paint were used? So, x%:y%:z%=1:y%:3 (1) x = y So the volume of green paint is of same % as blue, so green is also 1 gallon. (2) z = 60 x%:y%:z%=1:y%:3......... x%:y%:60%=1:y%:3 If 60% is 3, total = \(\frac{3*100}{60}=5\) So green= totalbluered=531=1 gallon D
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Re: A paint mixture was formed by mixing exactly 3 colors of paint. By vol
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27 Apr 2019, 09:31
[quote="Bunuel"]A paint mixture was formed by mixing exactly 3 colors of paint. By volume, the mixture was x% blue paint, y% green paint, and z% red paint. If exactly 1 gallon of blue paint and 3 gallons of red paint were used, how many gallons of green paint were used? (1) x = y (2) z = 60 Target question: How many gallons of green paint were used? Given: A paint mixture was formed by mixing exactly 3 colors of paint. By volume, the mixture was x% blue paint, y% green paint, and z% red paint. 1 gallon of blue paint and 3 gallons of red paint were used. In other words, we have: 1 gallon of BLUE paint representing x% of the mixture 3 gallons of RED paint representing z% of the mixture ? gallons of GREEN paint representing y% of the mixture Statement 1: x = y In other words, BLUE paint and GREEN paint comprise the same PERCENTAGE of volume in the mixture This means the volume of BLUE paint in the mixture = the volume of GREEN paint in the mixture Since we know there's 1 gallon of BLUE paint in the mixture, we must also have 1 gallon of GREEN paint in the mixture Since we can answer the target question with certainty, statement 1 is SUFFICIENT Statement 2: z = 60In other words, RED paint comprises 60% of the mixture In other words, 3 gallons of RED paint = 60% of the mixture's TOTAL volume It also means that 1 gallon of BLUE paint = 20% of the mixture's TOTAL volume This means the REMAINING 20% of the mixture must be GREEN paint. We already know that 1 gallon = 20% of the mixture So, we must also have 1 gallon of GREEN paint in the mixture Since we can answer the target question with certainty, statement 2 is SUFFICIENT Answer: D Cheers, Brent
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Re: A paint mixture was formed by mixing exactly 3 colors of paint. By vol
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14 May 2019, 19:28
Hi All, We're told that a paint mixture was formed by mixing exactly 3 colors of paint. By volume, the mixture was X% blue paint, Y% green paint, and Z% red paint and exactly 1 gallon of BLUE paint and 3 gallons of RED paint were used. We're asked for the number of gallons of green paint that were used. This question is built around 'System math' and has a great, builtin math shortcut that we can take advantage of.... To start, since there are only 3 colors in the mixture  and each color represents a certain percentage of the total, we can create the following equation: X + Y + Z = 100. In addition, we know exactly how much blue paint and red paint were used, so we can create a second equation (based around the percentages)  we used 3 times the amount of RED paint as BLUE paint, so... Z = 3X We now have 3 variables and 2 unique equations. If we have a third unique equation, then we'll have a System of equations and can solve for all 3 variables  meaning that we COULD answer the question that's asked (and without actually having to do all of that math). (1) X = Y Fact 1 gives us a third unique equation, so COULD determine the amount of green paint. Fact 1 is SUFFICIENT (2) Z = 60 Fact 2 also gives us a third unique equation, so COULD determine the amount of green paint. Fact 2 is SUFFICIENT Final Answer: GMAT assassins aren't born, they're made, Rich
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Re: A paint mixture was formed by mixing exactly 3 colors of paint. By vol
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17 May 2019, 13:54
Bunuel wrote: A paint mixture was formed by mixing exactly 3 colors of paint. By volume, the mixture was x% blue paint, y% green paint, and z% red paint. If exactly 1 gallon of blue paint and 3 gallons of red paint were used, how many gallons of green paint were used?
(1) x = y (2) z = 60
DS24751.01 OG2020 NEW QUESTION Let \(B\), \(G\), and \(R\), be the amounts of blue, green, and red paint used, respectively. We know that \(x+y+z=100\) and \(B:G:R=x:y:z=1:G:3\). The original question: \(G=?\) 1) We know that \(x=y\). \(x:y=1:1 \implies \frac{1}{1}=\frac{1}{G} \implies G=1\) Thus, the answer to the original question is a unique value. \(\implies\) Sufficient2) We know that \(z=60\). \(\frac{z}{x+y}=\frac{3}{1+G}\) \(\frac{60}{40}=\frac{3}{1+G}\) Thus, we could get a unique value to answer the original question. \(\implies\) SufficientAnswer: D
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Re: A paint mixture was formed by mixing exactly 3 colors of paint. By vol
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18 May 2019, 00:25
i dont understand how "if the BLUE paint and GREEN paint comprise the same PERCENTAGE of volume in the mixture then this means the volume of BLUE paint in the mixture = the volume of GREEN paint in the mixture"
can someone kindly explain this more please



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Re: A paint mixture was formed by mixing exactly 3 colors of paint. By vol
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18 May 2019, 10:05
rnn wrote: i dont understand how "if the BLUE paint and GREEN paint comprise the same PERCENTAGE of volume in the mixture then this means the volume of BLUE paint in the mixture = the volume of GREEN paint in the mixture"
can someone kindly explain this more please Hi rnn, The prompt tells us "by volume, the mixture was X% blue paint, Y% green paint, and Z% red paint." This means that the mixture is made up of just these 3 colors and each color represents a certain amount of the total. IF two of the percentages are EQUAL, then the amount of paint of those 2 colors is also EQUAL. For example: If... the mixture is 10 total gallons and is 20% blue, 20% green and 60% red, then we have.... 2 gallons of blue, 2 gallons of green and 6 gallons of red. GMAT assassins aren't born, they're made, Rich
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Re: A paint mixture was formed by mixing exactly 3 colors of paint. By vol
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19 May 2019, 02:17
Hi Rich,
Thanks for the response. I was thinking the following.
1 gallon of BLUE paint representing x% of the mixture => \(\frac{xB}{100}=1\) 3 gallons of RED paint representing z% of the mixture => \(\frac{zR}{100}=3\) ? gallons of GREEN paint representing y% of the mixture => \(\frac{yG}{100}=?\)
Now even if i replace y with x in \(\frac{yG}{100}=?\), I will still not be able to get the answer. I will have \(\frac{G}{B}\), which is useless.
Kindly let me know where I am going wrong with this approach.
Thanks



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Re: A paint mixture was formed by mixing exactly 3 colors of paint. By vol
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16 Jun 2019, 03:31
Can someone explain this question in a simple manner? Why should I consider 1 and 3 given in the last sentence of the question, as ratios?



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Re: A paint mixture was formed by mixing exactly 3 colors of paint. By vol
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20 Jun 2019, 10:38
A paint mixture was formed by mixing exactly 3 colors of paint. By volume, the mixture was x% blue paint, y% green paint, and z% red paint. If exactly 1 gallon of blue paint and 3 gallons of red paint were used, how many gallons of green paint were used? So, x%:y%:z%=1:y%:3
(1) x = y So the volume of green paint is of same % as blue, so green is also 1 gallon.
(2) z = 60 x%:y%:z%=1:y%:3......... x%:y%:60%=1:y%:3 If 60% is 3, total = 3∗10060=53∗10060=5 So green= totalbluered=531=1 gallon
D



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Re: A paint mixture was formed by mixing exactly 3 colors of paint. By vol
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22 Oct 2019, 07:19
Bunuel wrote: A paint mixture was formed by mixing exactly 3 colors of paint. By volume, the mixture was x% blue paint, y% green paint, and z% red paint. If exactly 1 gallon of blue paint and 3 gallons of red paint were used, how many gallons of green paint were used?
(1) x = y (2) z = 60
DS24751.01 OG2020 NEW QUESTION 100%volume=x%volume+y%volume+z%volume volume=blue+green+red volume=(1)+green+(3) x%volume=1 z%volume=3 (1) x = y sufic.x%volume=1 then y%volume=1=green (2) z = 60 sufic.z%volume=60%volume=3…volume=3/3/5=15/3=5 volume=(1)+green+(3)…5=1+3+green…green=1 Answer (D)



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Re: A paint mixture was formed by mixing exactly 3 colors of paint. By vol
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18 Dec 2019, 01:53
Alternate Approach.
If Red Paint (Z) = 3 gallons and Blue Paint (X) = 1 gallons, therefore, as Z = 60%, Blue + Green = 40%.
As 60% is 3 gallons, 20% is 1 Gallons, Hence we can say that Blue paint is 20% and thus green paint is rest i.e 20%. Therefore Green Pain is also 1 gallons, as Blue Paint is 20% = 1 Gallon.




Re: A paint mixture was formed by mixing exactly 3 colors of paint. By vol
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