In a certain office, 50 percent of the employees are college graduates and 60 percent of the employees are over 40 years

[VJesus12]

In a certain office, 50 percent of the employees are college graduates and 60 percent of the employees are over 40 years old. If 30 percent of those over 40 have master's degrees, how many of the employees over 40 have master's degrees?

(1) Exactly 100 of the employees are college graduates.
(2) Of the employees 40 years old or less, 25 percent have master's degrees.

Answer: A

Source: Official Guide

[Brent@GMATPrepNow]

In a certain office, 50 percent of the employees are college graduates and 60 percent of the employees are over 40 years old. If 30 percent of those over 40 have master's degrees, how many of the employees over 40 have master's degrees?

(1) Exactly 100 of the employees are college graduates.
(2) Of the employees 40 years old or less, 25 percent have master's degrees.

Answer: A

Source: Official Guide

Let's say there is a TOTAL of 100 students at this college.

50 percent of the total number of students are freshmen.
# of freshmen = 50% of 100 = 50

20 percent of the fresh-men are enrolled in the school of liberal arts...
Number of liberal arts freshmen = 20% of 50 = 10

...and, of these, 30 percent are psychology majors...
Number of liberal arts freshmen who are psychology majors = 30% of 10 = 3

What percent of the students at the college are freshmen psychology majors enrolled in the school of liberal arts?
3/100 = 3%

Answer: A

Cheers,
Brent