How to find how many students passed both exams?

Question

Here is my question

In a class which has $36$ students, there are $26$ students who passed math and $20$ students who passed physics exam and $4$ students couldn't pass the both subjects.

Then, how do we find the students who passed the both exam?

Regards!

Answer 1

$36-4=32$ students passed one or the other.

$26+20-32=14$ passed both. See the diagram...

Hope it helps

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