Total balls initially equal 9, reducing to 8 on the second draw without replacement. (i) P(Red then Blue) = (4/9) x (5/8) = 20/72 = 5/18. (ii) P(2 Blue) = (5/9) x (4/8) = 20/72 = 5/18.
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: (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?
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Total balls = 4 Red + 5 Blue = 9. Since the first ball is not replaced, 8 balls remain for the second pick.
Tree diagram paths:
First branch splits into Red (4/9) and Blue (5/9).
From Red, second branches split into Red (3/8) and Blue (5/8).
From Blue, second branches split into Red (4/8) and Blue (4/8).
(i) P(Red then Blue) = (4/9) x (5/8) = 20/72 = 5/18 (approx 0.278).
(ii) P(2 Blue balls) = (5/9) x (4/8) = 20/72 = 5/18 (approx 0.278).
For more NCERT Solutions of Class 9 Ganita Manjari Chapter 7 The Mathematics of Maybe: Introduction to Probability Question Answer (2026-27)
https://www.tiwariacademy.com/ncert-solutions/class-9/maths/ganita-manjari-chapter-7/