Question

At a highschool, 36 students are taking either calculus or physics or both, and 10 students are taking both calculus and physics. If there are 31 students in the calculus class, how many students are in the physics class?

Answer 1

i think 15

Answer 2

Why?

Answer 3

Remember the formula
a union b= a+b- a ^b

lets say a is calculus and b is physics

36=31+b-10

solve for b