Question

A pizzeria offers 8 different ingredients on its pizza. Andy chooses 3 different ingredients from the 8 by drawing the names from a hat. What is the probability that Andy chooses either mushrooms or pepperoni or both among his three ingredients?

The answer is 9/14, but how do you get it?

Answer 1

You can do it this way:

Pr(either m or P or both)=1-Pr(neither M or P)

Pr(neither)=6/8*5/7*4/6= 120/336=40/112=20/56=10/28= 5/14

Pr(either m or P or both)=1-5/14=9/14

Answer 2

Thank you! I always forget you can minus the complement from 1.