Cardinality of Set Union/Examples/Student Subjects

Example of Use of Cardinality of Set Union
In a particular group of $75$ students, all studied at least one of the subjects mathematics, physics and chemistry.

All candidates attempted at least one of the questions.


 * $40$ students studied mathematics.
 * $60$ students studied physics.
 * $25$ students studied chemistry.

Also:
 * exactly $5$ students studied all $3$ subjects.

It follows that: