Question

a box contains 5 green pencils and 7 yellow pencils. two pencils are chosen at random from the box without replacement. what is the probability they are different colors

Answer 1

A box contains 5 green pencils and 7 yellow pencils.

Two pencils are chosen at random from the box without replacement.

=> There are two cases:

1st pick green & 2nd pick yellow: P = 5/12 x 7/11 = 0.265

1st pick yellow & 2nd pick green: P = 7/12 x 5/11 = 0.265

Add up both cases, the probability they are different colors:

P = 0.265 + 0.265 = 0. 53

Hope this helps!

:)