Lesson Logic problems - The answer to Problem 4

The answer to Problem 4

Below (after the reminder) is the answer to the Problem 4 of the lesson Some logic problems (the topic Miscellaneous word problems
of the section Word problems in this site).

Problem 4 formulation (reminder)
There are 25 students in the class.
Each student attends a sport class or an art school. Some of students attend both a sport class and an art school.
Number of the students attending a sport class is 18; number of the students attending an art school is 12.
How many of class students attend both a sport class and an art school?

Answer
The number of students attending both a sport class and an art school is equal to 5.

Back to the original lesson Some logic problems (the topic Miscellaneous word problems of the section Word problems in this site).
Go to the solution (the topic Miscellaneous word problems of the section Word problems in this site).