Question

A box contains 20 balls: 10 are yellow , 6 are red and 4 are grey. What is the probability of picking a yellow and then a red ball without replacing the first

Answer 1

3/19

Explanation:

A box contains 20 balls: 10 are yellow , 6 are red and 4 are grey.

P(yellow) = yellow balls / total balls

= 10/20 = 1/2

Now there are only 19 balls: 9 are yellow , 6 are red and 4 are grey.

P(red) = red balls/ total

=6/19

Multiply the two probabilites together

P(yellow) * P(red) = 1/2 * 6/19 = 3/19