Question

8 boys and 3 girls are to sit in a row for a photograph.find probability that no 2 girls are together?

Answer 1

Step-by-step explanation:

8 boys and 3 girls can be seated in 7! ways.

The 3 girls can be seated in 3! ways.

The 3 girls leave 2 gaps between them to seat any 2 boys while the remaining 2 boys will have to be seated at the 2 ends. Thus the 4 boys can be seated in the available 4 places in 4! ways.

Hence required probability= 3!*4!/7!= 1/35.