Question

Let x, y, and z be values so that x = P(A), y = P(B), and z = P(A and B), where A and B are two events. Express the value of P(A or B) in terms of x, y, and z

Answer 1

$\mathbb P(A\cup B)=\mathbb P(A)+\mathbb P(B)-\mathbb P(A\cap B)=x+y-z$