The girls basketball team has 12 players. If the coach chooses 5 girls to play at a time, how many different teams can be formed?
A box contains 3 red marbles, 6 blue marbles, and 1 white marble. The marbles are selected at random, one at a time, and are not replaced. What is the probability of selecting a red and a white and blue?
A box contains 3 red marbles, 6 blue marbles, and 1 white marble. The marbles are selected at random, one at a time, and are not replaced. What is the probability of selecting a red and a white and blue?
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a) 12C5 = (12x11x10x9x8x7)/5! = 792 (since order does not matter)
b) there are 3x6x1 = 18 ways to select one marble of each color, out of 10C3 = 120 ways to select 3 marbles from 10 without replacement. so the probability is 18/120 = 3/20
b) there are 3x6x1 = 18 ways to select one marble of each color, out of 10C3 = 120 ways to select 3 marbles from 10 without replacement. so the probability is 18/120 = 3/20
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1. 12 C 5 or 12 x 11 x 10 x 9 x 8
2. 1/10 x 6/10 x 3/10
2. 1/10 x 6/10 x 3/10