1. Class 12
  2. Solutions of Sample Papers and Past Year Papers - for Class 12 Boards
  3. CBSE Class 12 Sample Paper for 2020 Boards

Question 7 - CBSE Class 12 Sample Paper for 2020 Boards

Last updated at Oct. 17, 2019 by

An urn contains 6 balls of which two are red and four are black. Two balls are drawn at random. Probability that they are of the different colours is

(a) 2/5                (b) 1/15             (c) 8/15           (d) 4/15

Slide14.JPG

Slide15.JPG

  1. Class 12
  2. Solutions of Sample Papers and Past Year Papers - for Class 12 Boards

    3. CBSE Class 12 Sample Paper for 2020 Boards

    CBSE Class 12 Sample Paper for 2019 Boards →

Transcript

Question 7 An urn contains 6 balls of which two are red and four are black. Two balls are drawn at random. Probability that they are of the different colours is (a) 2/5 (b) 1/15 (c) 8/15 (d) 4/15 P(they are of different colors) = P(first ball drawn is black) × P(second ball drawn is red) + P(first ball drawn is red) × P(second ball drawn is black) = 4/6 × 2/5 + 2/6 × 4/5 = 8/30+8/30 = 16/30 = 𝟖/𝟏𝟓 ∴ The correct answer is (c) = 8/15 1 mark

Class 12
Solutions of Sample Papers and Past Year Papers - for Class 12 Boards

About the Author

Davneet Singh's photo - Teacher, Computer Engineer, Marketer
Davneet Singh
Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 9 years. He provides courses for Maths and Science at Teachoo.