Try this solution: 1. Probability (P): 1-[probability_all_the_girls] 2. P=1- 1/2⁶=1- 1/64=63/64≈0.984375.
Note: P_all_the_g=[needed_cases]/[all_possible_cases], where needed cases=1 (all the girls means 'gggggg'), and all possible cases=2⁶=64 (all possible cases means 'gggggg';'bbbbbb';gbbbbb';'ggbbbb';'gggbbb';'ggggbb';gggggb';'bggggg', etc. Total 64 combinations.)
