Solution

We do have 9000 splits into 3 parts: students from C, students NOT from C , and not students at all.

We can name them as \(x+y+z=9000\)

So \(z= 9000 - x - y\)

So the best answer is \(C\)
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Another approach is to use the Double Matrix Method. This technique can be used for most questions featuring a population in which each member has two characteristics associated with it (aka overlapping sets questions).
Here, we have a population of people watching a football game, and the two characteristics are:
- from College C or not from College C
- student or non student

We can set up out diagram as follows:



Since the two columns (student and non-student) must add to 9000, the SUM of the two boxes in the non-student column must = 9000 - (x + y)
= 9000 - x - y

So, we get:
Quantity A: 9000 - x - y
Quantity B: 9000 - x - y

Answer: C

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Answer is c

can B be the answer/

In a question like this, would it be possible for the number of students not from college C to be 0? (Kind of as a trick question)

No. Impossible.

The question then would not make any sense.

Regards
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