A basket contains 4 red balls and 5 blue balls. One ball is drawn and laid aside, and a second ball is drawn. Class 9

A basket contains 4 red balls and 5 blue balls. One ball is drawn and laid aside, and a second ball is drawn. Class 9

Question 1.

A basket contains 4 red balls and 5 blue balls. One ball is drawn and laid aside, and a second ball is drawn. Draw a tree diagram to represent the possible outcomes and probabilities. Use the tree diagram to answer the following questions. Class 9

i. What is the probability of drawing a red ball and then a blue ball?

ii. What is the probability of drawing 2 blue balls?

Solution:

i. P(drawing a red then a blue ball) = P(1^st Red) × P(2^nd Blue) = $\frac{4}{9} \times \frac{5}{8}=\frac{5}{18}$

ii. P( 2 blue balls) = P(1^st Blue) × P(2^nd Blue) = $\frac{5}{9} \times \frac{4}{8}=\frac{5}{18}$