All trainees in a certain aviator training program must take both a wr

Total = A + B - Both + Neither
1) 100 = 70 + 80 - Both + 10, so, Both = 60. Sufficient.

2) Since, 20 percent of the trainees passed the flight test, the remaining 60 percent must have passed the both test. Sufficient.

D is the answer.

Please find attached the reply.

Answer D as both the statements are sufficient.

Solution:

Question Stem Analysis:

We can use the formula:

Total = Pass Written + Pass Flight - Pass Both + Pass Neither

With “Total” = 100, we are given “Pass Written” = 70 and “Pass Flight” = 80, and we need to find “Pass Both.” That is,

100 = 70 + 80 - B + N

B = 50 + N

If we know the value of N (“Pass Neither”), then we can determine the value of B (“Pass Both”).

Statement One Only:

10 percent of the trainees did not pass either test.

Since we are given that N = 10, we have:

B = 50 + 10 = 60

Statement one alone is sufficient.

Statement Two Only:

20 percent of the trainees passed only the flight test.

This means “Pass Only Flight” = 20. Since Pass Both = Pass Flight - Pass Only Flight, we have B = 80 - 20 = 60.

Statement two alone is sufficient.

Answer: D

Total=Written+Flight-Both+Neither

(1) 100=70+80-Both+10 Sufficient.

(2) 80-20=60 Both; Sufficient

The answer is D

We are assuming that the total number of trainees are 100. What is the assumed the total number of trainees as 200? The answer would change. Can someone explain this?

All trainees in a certain aviator training program must take both a written test and a flight test. If 70 percent of the trainees passed the written test, and 80 percent of the trainees passed the flight test, what percent of the trainees passed both tests?

Trainees are given in percentage form. Percentage means 100%
If you think the total is 200 then you have double 140 percent for written test and 160 percent for flight test.

Thank you for asking.

Another way to think about such questions:
1. For the first condition, the universe involves you knowing the actual (person-wise) total of total 'passers'. SO the number of 90 is crucial to know (which we can figure out from the value of 10 that is basically both fail). Here, the universe actually depends on the both failure number, since that is what determines how big your-either-subject pass bucket is.

2. The second question has its universe limited to only the Flight test folks, so it is NOT crucial to know the other info (number of both fails) -> it is a straight forward condition involving only flight pass and flight and written test.

Answer: Option D

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