Question

A box contains 2 red coins, 3 green coins and 4 blue coins. in how many ways can 3 coins be chosen such that at least one coin is green?​

Answer 1

Answer:

Okay there are total 9C3 = 84 ways to choose coins .

Let calculate cases when

There is no green coins appears or all three coins are chosen from 2 red + 4 blue = 6 coins, there will be 6C3 = 20 ways .

So ways when there is atleast one green coin is

= 84 - 20 = 64