First,we would list out the possibilities to find the probability:
Let G represent girl and B represent boy,here are the possibilities:
1)GGGGGG
2)GBBBBB
3)GGBBBB
4)GGGBBB
5)GGGGBB
6)GGGGGB
7)BBBBBB
Since there are 7 probabilities,the probability is 1/7.
Hope it helps!
