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


Number of girls in a family



2



1



0



Number of families



475



814



211



Compute the probability of a family, chosen at random, having


(i) 2 girls


(ii) 1 girl


(iii) No girl


Also check whether the sum of these probabilities is 1.


Total number of families = 1500

(i) Numbers of families having two girls = 475


Probability of families having two girls will be,



(ii) Number of families having one girl = 814


Probability of families having one girl will be,



(iii) Number of families having zero girl = 211


Probability of families having zero girl will be,



Sum of probabilities



Hence,


Yes, the sum of these probabilities is 1.


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