Question 986422
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If all that matters is the number of B's and G's, the answer is 8,
0 girls to all 8 girls one at a time.
If order matters:
2 x 2 x 2 x 2 x 2 x 2 x 2=2^7=128
This is the number of all possible 7 place strings with B or G in each place.