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# The Quest for 700: Weekly GMAT Challenge (Answer)

Yesterday, Integrated Learning posted a 700 level GMAT question on our blog. Today, they have followed up with the answer:

Ans: A

To answer this question, you can do the math, or you can rely on the experience you have gained thus far.  Let’s work out statement 1 by thinking it through:

Statement 1: We know there are a specific number of girls (q).  Since each number of girls would yield a different probability of choosing 2 girls, there must be only one specific number that would yield 1/11.  So it must be enough information.

Now, statement 2 requires a little more thought.  Let’s work it out by doing the math:
Statement 2: This one may seem to follow the same logic, as they are giving us a specific probability.  However, this time we are asked to pick one boy and one girl.  Look at the following chart to see why this isn’t enough information:

*As you can see, each probability is repeated for inverse combinations of boys and girls.  There are two ways to get 16/33, once with 4 boys and 8 girls, and also with 4 girls and 8 boys.  This is not enough information.  We do not know what q is.

*Note: we will multiply each probability by 2, because we can choose a boy and a girl, or a girl and a boy, and both will yield the desired result.

Integrated Learning provides professional, experienced GMAT tutors throughout the United States.