Two chocolates need to be picked from a box with replacement.

Question

Two chocolates need to be picked from a box with replacement. If all the chocolates in the box are wrapped in either green or blue wrapper. Then what's the probability that we get one chocolate of each color.

(1) The probability of getting chocolates of the same color is 5/9
(2) The number of chocolates with a blue wrapper is twice the number of chocolates with a green wrapper

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stne · Answer

(1) The probability of getting chocolates of the same color is 5/9

Prob. of not getting same color =  1- \frac{5}{9} = \frac{4}{9}

SUFF.

(2) The number of chocolates with a blue wrapper is twice the number of chocolates with a green wrapper

Let it be  x  and  2x  respectively.

Therefore  \frac{x}{3x}*\frac{2x}{3x}*2! =\frac{4}{9}  We multiply by  2  because we don't know which color will be picked first. We could pick BG or GB.

SUFF.

Ans D

Hope it helped.

Gemmie · Answer

Two chocolates need to be picked from a box  with replacement

(1) The probability of getting chocolates of the same color is   \frac{5}{9}

=> The probability that we get one chocolate of each color =  1 - \frac{5}{9} = \frac{4}{9}

(2) The number of chocolates with a blue wrapper is twice the number of chocolates with a green wrapper

B = 2G => Total (B+G) = 3G

\frac{B}{B+G} = \frac{2}{3}

\frac{G}{B+G} = \frac{1}{3}

The probability of getting chocolates of the same color

=  (\frac{B}{B+G})^2 + (\frac{G}{B+G})^2

=  (\frac{2}{3})^2 + (\frac{1}{3})^2

=  \frac{5}{9}

Like statement 1, we can infer the probability that we get one chocolate of each color

gullyboy09 · Answer

I think we can do this question orally. If you read carefully, we just need the ratio of blue/green wrap.

Now for the (1), there can be only one unique value of the ratio (blue/green) can exist so that the P of both same color is 5/9. So it should be sufficient.
Second is straight forward, it already tells us the ratio.

Two chocolates need to be picked from a box with replacement.

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GMAT Data Sufficiency (DS) Questions

Two chocolates need to be picked from a box with replacement.

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

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