How many of the boys in a group of 100 children have brown hair?

[Vincen]

How many of the boys in a group of 100 children have brown hair?

(1) Of the children in the group, 60 percent have brown hair.
(2) Of the children in the group, 40 are boys.

[spoiler]OA=E[/spoiler]

Source: Official Guide

[Jay@ManhattanReview]

How many of the boys in a group of 100 children have brown hair?

(1) Of the children in the group, 60 percent have brown hair.
(2) Of the children in the group, 40 are boys.

[spoiler]OA=E[/spoiler]

Source: Official Guide

So there are a few boys and a few girls, making 100 in total.

Let's take each statement one by one.

(1) Of the children in the group, 60 percent have brown hair.

We do not know how many are boys and how many girls are there. Insufficient.

(2) Of the children in the group, 40 are boys.

We do not know out of 40, how many boys have brown hair. Insufficient.

(1) and (2) together

Even both statements together are insufficient for we do not know out of 40 boys, what percent of boys have brown hair. Though statement 1 gives that 60 percent have brown hair, it doe not mean that 60 percent of boys, too, have brown hair.

Correct answer: E

Hope this helps!

-Jay
_________________
Manhattan Review GMAT Prep

Locations: Manhattan GMAT | GRE Practice Questions | LSAT Practice Test | SAT Info | and many more...

Schedule your free consultation with an experienced GMAT Prep Advisor! Click here.