Past Year MCQ

Chapter 14 Class 10 Probability
Serial order wise

## (c) 4/45                                                           (d) 9/89

### Transcript

Question 1 A box contains 90 discs, numbered from 1 to 90. If one disc is drawn at random from the box, the probability that it bears a prime-number less than 23, is: (a) 7/90 (b) 10/90 (c) 4/45 (d) 9/89 Total number of disks = 90 Prime number less than 23 areβ¦ 2, 3, 5, 7, 11, 13, 17, 19 Number of prime numbers less than 23 = 8 Thus, P(getting a prime number less than 23) = (ππ’ππππ ππ πππππ ππ’πππππ  πππ π  π‘βππ 23)/(πππ‘ππ ππ’πππππ ) = 8/90 = π/ππ So, the correct answer is (C)

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#### Davneet Singh

Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 14 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.