Vincen wrote:How many members of Group G are less than 25 years of age?

(1) Exactly 3/5 of the members of Group G are 25 years of age or older.
(2) The 24 men in Group G constitute 30 percent of the groups membership

OA is C.

What should be the reasoning in this exercise? How can I solve it?

We have to determine the members of Group G that are less than 25 years of age.

Statement 1: Exactly 3/5 of the members of Group G are 25 years of age or older.

Since 3/5 of the members of Group G are 25 years of age or older, it means that (1 - 3/5 =) 2/5 members of Group G are less than 25 years of age.

We do not know the total number of members. We cannot get the answer. Insufficient.

Statement 2: The 24 men in Group G constitute 30 percent of the group membership.

Since 24 men in Group G constitute 30 percent of the group membership, it means that total number of members = 24 / 30% = 24*(100 / 30) = 80.

This cannot help as we do not know how many of them are less than 25 years of age. Insufficient.

Statement 1 and 2:

From (1), we know that 2/5 members of Group G are less than 25 years of age, and from (2), we know that the total number of members equals to 80.

Thus, the members of Group G that are less than 25 years of age = (2/5)*80 = 32. Sufficient.

The correct answer: C

Hope this helps!

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