In a garden 40% of the flowers are roses and rest are carnations. If

Question

In a garden 40% of the flowers are roses and rest are carnations. If 1/4 of the roses and 1/10 of carnations are red, what is the probability that a red flower selected at random is a rose?

A. 1/17
B. 5/8
C. 2/3
D. 3/4
E. 7/9

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fall2021 · Answer

Shouldn't the question be what is the probability that a red flower selected randomly is rose?

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Bunuel · Answer

___________________
Yes. Fixed. Thank you

fall2021 · Answer

Assuming there are 100 flowers, we can see by given information that there are 40 roses and 60 carnations.

Of the 40 roses, 1/4 are red, so there are 10 red roses.

Of the 60 carnations, 1/10 are red, so there are 6 red carnations.

P(Rose|Red) = 10/(10+6) = 5/8

Option B

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Vivor · Answer

Let there be 100 flowers

40% are roses
So, No. of roses = 40
and, No. of carnations = 100-40 = 60

\frac{1}{4}  of roses are red => No. of Red Roses =  \frac{1}{4}*40  = 10
 \frac{1}{10}  of carnations are red => No. of Red Carnations =  \frac{1}{10}*60  = 6

Hence, no. of red flowers = 10+6 = 16
Ans =  \frac{No. of Red Roses}{No. of Red flowers} = \frac{10}{16} = \frac{5}{8}

Ans is B IMO

GMATinsight · Answer

Let, total flowers =100

Roses = 40
Carnations = 60

1/4 of the roses and 1/10 of carnations are red
i.e. Red = (1/4)*40+(1/10)*60 = 16

probability that a red flower selected at random is a rose = Red Roses / red Flowers = 10/16 = 5/8

ANswer: Option B

CEdward · Answer

P(rose) = 2/5
P(carnation) = 3/5

1/4 x 2/5 = 1/10 of roses are red
1/10 x 3/5 = 3/50 of carnations are red

P(red rose) = 1/10 / (1/10 + 3/50) = 1/10 / 8/50 = 1/10 x 25/4 = 25/40 = 5/8

B.

CrackverbalGMAT · Answer

SOLUTION:

Let their be "x" flowers

Number of roses = 40% = 0.4x

Number of carnations = 100-40=60% = 0.6x

1/4 of the roses = 1/4 * (0.4x) = 0.1x and

1/10 of carnations = 1/10 * (0.6x) = 0.06x are RED

Probability that a red flower selected at random is a rose= 0.1x / 0.16x

= 5/8 (OPTION B)

Hope this helps

Devmitra Sen(Math)

ScottTargetTestPrep · Answer

Solution:
 
We can let the number of flowers be 100. So there are 40 roses and 60 carnations. Of the 40 roses, 10 are red, and of the 60 carnations, 6 are red. Therefore, the probability that a red flower selected at random is a rose is 10 / (10 + 6) = 10/16 = 5/8.

Answer: B

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