Question

Two urns each contain green balls and blue balls. urn i contains 4 greenballs and 6 blue balls, and urn ii contains 6 green balls and 2 blueballs. a ball is drawn at random from each urn. what is the probabilitythat both balls are blue?

Answer 1

1st urn....4 green balls, 6 blue balls.....10 total balls....probability of drawing a blue ball in urn 1 is : 6/10 reduces to 3/5

2nd urn...6 green balls, 2 blue balls....8 total balls...probability of drawing a blue ball in urn 2 is : 2/8 reduces to 1/4

probability both balls are blue : 3/5 * 1/4 = 3/20 <==