Mathematics 2003 JAMB Past Questions - Question 48: A bag contains 5 black balls and 3red balls.Two balls are picked randomly without replacement .What is the probability that a black and red ball are picked?

Correct Answer

A

Explanation

To find the probability of picking a black and a red ball, we need to calculate the probability of each event separately and then multiply them together.First, let's calculate the probability of picking a black ball on the first draw. There are 5 black balls out of a total of 8 balls in the bag, so the probability of picking a black ball on the first draw is 5/8.After picking a black ball on the first draw, there will be 4 black balls and 3 red balls left in the bag. Now, let's calculate the probability of picking a red ball on the second draw. There are 3 red balls out of a total of 7 balls remaining in the bag, so the probability of picking a red ball on the second draw is 3/7.To find the probability of both events happening, we multiply the probabilities together:Probability of picking a black and a red ball = (5/8) * (3/7) = 15/28Therefore, the probability of picking a black and a red ball is 15/28