Similarly, if I know there are 75 people in event space A B, and also know there are 40 people in all of A and 50 people in all of B I can let X be value of A B and build the Aonly space as the total in A subtracted by the number in the intersecon, X. Doing the same for event space B, I get the diagram below. B. Set up an equaon and find the value of A B