Question

There are 37 students participating in an after-school program offering classes in yoga, bridge, and painting. Each student must take at least one of these three classes, but may take two or all three. There are 12 students taking yoga, 18 taking bridge, and 19 taking painting. There are 9 students taking at least two classes. How many students are taking all three classes

Answer 1

3

Explanation:

I added the number of students enrolled in each class. It equaled 49.

I subtracted the number of students from that amount

49-37= 12

I subtracted the number of students enrolled in two or more classes

12-9= 3

3 are enrolled in 3 classes

Answer 2

Answer: 3 students

Explanation:

You can solve this using the expression;

Total = A + B + C - Both - all - neither

Where A, B and C represent those taking one class

As each student must take at least 1 class, there is no 'neither'.

37 = 12 + 18 + 19 - 9 - All

37 = 40 - All

All = 40 - 37

All = 3