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

An urn contains 6 balls of which two are red and four are black

Question 7 - CBSE Class 12 Sample Paper for 2020 Boards - Part 2

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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

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Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 13 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.