rose problem

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rose problem

by AIM TO CRACK GMAT » Tue Dec 18, 2012 1:26 am
At the end of the day, February 14th, a florist had 120 roses left in his shop, all of which were red, white or pink in color and either long or short-stemmed. A third of the roses were short-stemmed, 20 of which were white and 15 of which were pink. The percentage of pink roses that were short-stemmed equaled the percentage of red roses that were short-stemmed. If none of the long-stemmed roses were white, what percentage of the long-stemmed roses were red?




20% 25% 50% 75% 80%

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by aman88 » Tue Dec 18, 2012 2:00 am
IMO B.

*The grid form may work out well here.

Please confirm the answer.
Thanks.

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by Sam_hellboy » Tue Dec 18, 2012 2:27 am
Red White Pink Total
Long 80 - X 0 X 80
Short 5 20 15 40
Total 85 - X 20 15+x 120

got the above table with the given data.

Now % short stemed for Red & Pink are equal.
hence

5/(85-x) = 15/(15+x)

Solving the above we get x = 60.
Now no of Long stem red flower = 80 -x = 80 - 60 = 20
% = 20/80 * 100 = 25%

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by GMATGuruNY » Tue Dec 18, 2012 3:54 am
AIM TO CRACK GMAT wrote:At the end of the day, February 14th, a florist had 120 roses left in his shop, all of which were red, white or pink in color and either long or short-stemmed. A third of the roses were short-stemmed, 20 of which were white and 15 of which were pink. The percentage of pink roses that were short-stemmed equaled the percentage of red roses that were short-stemmed. If none of the long-stemmed roses were white, what percentage of the long-stemmed roses were red?

20% 25% 50% 75% 80%
Use a GROUP GRID to organize the data.

A florist had 120 roses left in his shop, all of which were red, white or pink in color and either long or short-stemmed.
A third of the roses were short-stemmed:


........L........S........T

R

W

T.....80.....40......120



Of the short-stemmed roses, 20 were white and 15 were pink.
None of the long-stemmed roses were white:


........L........S........T

R................5

W......0.......20.....20

P................15

T.....80......40.....120



The percentage of pink roses that were short-stemmed equaled the percentage of red roses that were short-stemmed.
This is the equivalent of the following ratio:

long red : short red = long pink : short pink
long red : 5 = long pink : 15
long red : long pink = 5:15 = 1:3.

The grid indicates that (long red) + (long pink) = 80.
Since 1:3 = 20:60, long red = 20 and long pink = 60.
Thus:
(long red) / (total long) = 20/80 = 1/4 = 25%.

The correct answer is B.
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Re: rose problem

by himadeepm » Mon Aug 17, 2020 2:33 am
i Believe this could be solved better with tabular approach