Question

1000 families with 2 children were selected randomly , and the following data were recorded : 

Number of girls in a family	0	1	2
Number of families	333	392	275

Find the probability of a family , having
(ii) 2 girls

Answer 1

Total number of families = 333 + 392 + 275 = 1000 

(ii) Number of families having 2 girl = 275 

`"Required probability" = "Number of families having 1 girls"/"Total number of families"`

 = `275/1000 = 11/40`