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Work Shown:
A = probability of getting a yellow ball
A = (number of yellow)/(number total)
A = 7/(5+7+1)
A = 7/13
B = probability of getting a green ball after event A happens, no replacement
B = (number of green)/(number left after the yellow is picked)
B = 5/(13-1)
B = 5/12
A*B = probability of getting yellow followed by green, no replacement
A*B = (7/13)*(5/12)
A*B = (7*5)/(13*12)
A*B = 35/156
