Probability 10 balls, the ball breaks
ball 3 red • green • blue 2 ball roller • 2
•
3 other color balls to grab out 3 balls at the same time, Sam Maple space is equivalent to a selection of 3 pieces from 10 pieces 7
n (S) = (103)
n count (E)
.He wants to come out at the same time 3 balls "were red and green, each ball and not blue," which he would have been as follows:
• Red 1 ball 1 ball green
• • other color balls 1
therefore that there must be 3 steps is
1. Select all red balls from ball 1 3
2. 1. all the balls from the ball 2
3. Select a color from ball 1 3 all other ball
, which is working to do all three jobs in order to finish (grab three balls), so use the multiplication rules
n (E) ==== (31) × (21) × (31) 3 1 2 × 2!?!?!?! 1! 1! 1! 3 × 2!?!3 × 2 × 318
P
P (E) computation (E) n ====== (E) n (S) 18 (103) 1810! 7 3 9 × × 1810!! 83 × 118 × 2 × 3 × 210 × 9 × 8320
answer = P (E) = 320 640
knowledge: probability
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