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In a garden, there are three blue flowers, three red flowers, three
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06 Apr 2016, 06:03
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In a garden, there are three blue flowers, three red flowers, three green flowers, and three pink flowers. What is the probability that a florist will choose three flowers of the same color when randomly picking three flowers? A. 11/10 B. 1/55 C. 31/10 D. 3/55 E. 1/16
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Re: In a garden, there are three blue flowers, three red flowers, three
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06 Apr 2016, 08:46
Total number of ways to pick 3 flowers out of 12 = 12c3 \(12c3 = \frac{12!}{9!*3!} = 220\) Total number of favorable outcomes = 4 (Only 3 flowers per colour, so there is only one way all three flowers of any particular colour can be chosen. 4 colours mean 4 favorable outcomes) Probability = \(\frac{4}{220} = \frac{1}{55}\) Answer: B Alternatively, if you like the slot method, the first flower can be chosen at random, it doesn't matter. The second flower must be the same colour as the first  probability = 2/11. The third flower must be the same colour as the first two  probability = 1/10. \(\frac{2}{11}*\frac{1}{10} = \frac{1}{55}\)
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Re: In a garden, there are three blue flowers, three red flowers, three
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06 Apr 2016, 10:55
Bunuel wrote: In a garden, there are three blue flowers, three red flowers, three green flowers, and three pink flowers. What is the probability that a florist will choose three flowers of the same color when randomly picking three flowers?
A. 11/10 B. 1/55 C. 31/10 D. 3/55 E. 1/16 P(all the same color) = P(1st flower is ANY color AND 2nd flower is same as first AND 3rd flower is also the same color) = P(1st flower is ANY color) x P(2nd flower is same as 1st) AND P(3rd flower is the same color) = 1 x 2/11 x 1/10 = 1/55 Answer: B Related ResourcesThe following free videos cover the concepts/strategies that are useful for answering this question:  Probability of Event A AND Event B: https://www.gmatprepnow.com/module/gmat ... /video/750  Rewriting Questions: https://www.gmatprepnow.com/module/gmat ... /video/754 Cheers, Brent
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Re: In a garden, there are three blue flowers, three red flowers, three
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12 Apr 2016, 04:50
R: !!! B: !!! G: !!! P: !!! ways of selecting a color : 4C1 ways of selecting the three flowers within the chosen color: 3C3 ways of selecting three flowers out of 12 : 12C3 \(\frac{(4C1*3C3)}{12C3} = \frac{1}{55}\)
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Re: In a garden, there are three blue flowers, three red flowers, three
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27 Apr 2016, 01:05
I am a novice in this giving solutions but is too tempted to explain the logic of this one. Overall I have 12 flowers and I need to select just 3 of the same colour out of 12. Let me select blue as my color so the first flower that I pick is blue in color and I can do that in 1 way now the second flower that I need to pick should also be blue in color so I can choose any one out of remaining two blue flowers 2/11 and finally I can choose the last blue flower in 1/10 way So yeah Overall P(z)= 1/55



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In a garden, there are three blue flowers, three red flowers, three
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03 Jul 2016, 09:21
Bunuel wrote: In a garden, there are three blue flowers, three red flowers, three green flowers, and three pink flowers. What is the probability that a florist will choose three flowers of the same color when randomly picking three flowers?
A. 11/10 B. 1/55 C. 31/10 D. 3/55 E. 1/16 { B B B } , { R R R } , { G G G } , { P P P } = TOTAL 12 FLOWERSYou need 3 flowers , so total no of ways it is possible is \(12c3\) = 220 Now you need one particular colour of flowers from these set... So, We can have it in 4 ways as the sets the flowers now represents sets as below  BLUE , RED , GREEN , PINK\(Probability\) = \(\frac{Favourable \ Outcome}{Total \ Possible \ Outcome}\) => \(\frac{4}{220}\) So, The answer will be (B)
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Re: In a garden, there are three blue flowers, three red flowers, three
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03 Jul 2016, 10:26
Bunuel wrote: In a garden, there are three blue flowers, three red flowers, three green flowers, and three pink flowers. What is the probability that a florist will choose three flowers of the same color when randomly picking three flowers?
A. 11/10 B. 1/55 C. 31/10 D. 3/55 E. 1/16 Sent from my iPhone using GMAT Club Forum mobile app



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Re: In a garden, there are three blue flowers, three red flowers, three
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12 Jul 2017, 04:52
Bunuel wrote: In a garden, there are three blue flowers, three red flowers, three green flowers, and three pink flowers. What is the probability that a florist will choose three flowers of the same color when randomly picking three flowers?
A. 11/10 B. 1/55 C. 31/10 D. 3/55 E. 1/16 Total events = 12 C 3 (i.e. selecting any 3 flowers from total 12 flowers) = 12 x 11 x 10 / 3 / 2 = 2 x 11 x 10 No. of events in which 3 flowers selected will be of same colour = 4 (3 flowers of each colour say RRR, BBB, GGG, PPP) So required probability = 4/2/11/10 = 1/55 Answer B



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Re: In a garden, there are three blue flowers, three red flowers, three
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14 Jul 2017, 08:44
Bunuel wrote: In a garden, there are three blue flowers, three red flowers, three green flowers, and three pink flowers. What is the probability that a florist will choose three flowers of the same color when randomly picking three flowers?
A. 11/10 B. 1/55 C. 31/10 D. 3/55 E. 1/16 Hi Bunuel, Though I understood the solution, I could not get answer using this approach. Could you help me identify the problem in this approach? I tried like this  3B, 3R, 3G, 3P Now to choose 3 flowers of same colour (3C1*2C1*1C1) * 4/12C3 I am getting 6/55 Thank you so much for help.



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Re: In a garden, there are three blue flowers, three red flowers, three
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28 Nov 2019, 23:38
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Re: In a garden, there are three blue flowers, three red flowers, three
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