1.

Three boys and two girls stand in a queue. The probability, that the number of boys ahead is at least one more than the number of girls ahead of her, is (A) `1/2` (B) `1/3` (C) `2/3` (D) `3/4`A. `1//2`B. `1//3`C. `2//3`D. `3//4`

Answer» Correct Answer - A
Total number of ways to arrange 3 boys and 2 girls are 5!.
According to given condition, following cases may mise.
`{:(B" "G" "G" "B" "B),(G" "G" "B" "B" "B),(G" "B" "G" "B" "B),(G" "B" "B" "G" "B),(B" "G" "B" "G" "B):}`
So number of favorite ways `=5xx3!xx2!=60`
`therefore " Required probility " =(60)/120)=1/2`


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