RD Sharma Solutions Class 9 Mathematics Solutions for Probability Exercise 25.1 in Chapter 25 - Probability

Question 1 Probability Exercise 25.1

1500 families with 2 children were selected randomly, and the following data were recorded:

no. of girls in a family	0	1	2
no. of girls	211	814	475

If a family is chosen at random, compute the probability that it has: (i) No girl (ii) 1 girl (iii) 2 girls (iv) At most one girl (v) More girls than boys

Answer:

We know, Probability of an event = (Number of Favorable outcomes) / (Total Numbers of outcomes) In this case, total numbers of outcomes = 211 + 814 + 475 = 1500. (Here, total numbers of outcomes = total number of families) (i) Probability of having no girl = 211/1500 = 0.1406 (ii) Probability of having 1 girl = 814/1500 = 0.5426 (iii) Probability of having 2 girls = 475/1500 = 0.3166 (iv) Probability of having at the most one girl = (211+814) /1500 = 1025/1500 = 0.6833 (v) Probability of having more girls than boys = 475/1500 = 0.31