BTGModeratorVI wrote: ↑Thu Aug 27, 2020 12:13 pm
In a certain corporation, there are 300 male employees and 100 female employees. It is known that 20% of the male employees have advanced degrees and 40% of the females have advanced degrees. If one of the 400 employees is chosen at random, what is the probability this employee has an advanced degree or is female?
A. 1/20
B. 1/10
C. 1/5
D. 2/5
E. 3/4
Answer:
D
Source: Magoosh
20% of the 300 male employees have advanced degrees and 40% of the 100 females have advanced degrees
20% of 300 = 60. So, there are 60 MALES with advanced degrees
40% of 100 =
40. So, there are
40 FEMALES with advanced degrees
Total number of advanced degrees = 60 +
40 = 100
So, P(selected person has advanced degree) = 100/400 =
1/4
Also, P(selected person is female AND has a advanced degree) =
40/400 =
1/10
Also, P(selected person is female) = 100/400 =
1/4
What is the probability the selected employee has an advanced degree or is female?
P(A or B) = P(A) + P(B) - P(A and B)
So, P(employee has advanced degree OR employee is female) =
P(employee has advanced degree) +
P(employee is female) -
P(selected person is female AND has a advanced degree)
=
1/4 +
1/4 -
1/10
= 2/4 - 1/10
= 2/5
Answer: D
Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
