SOLUTION: A box contains 5 red balls and 10 blue balls. A) How many samples of 3 balls are possible? B) How many samples will have all red balls? C) What is the probability the sample will h

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Question 478994: A box contains 5 red balls and 10 blue balls. A) How many samples of 3 balls are possible? B) How many samples will have all red balls? C) What is the probability the sample will have 3 red balls? D)What are the odds in favor of drawing a blue ball?
Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
A box contains 5 red balls and 10 blue balls.
A) How many samples of 3 balls are possible?;;15C3
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B) How many samples will have all red balls?::5C3
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C) What is the probability the sample will have 3 red balls?::5C3/15C3
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D)What are the odds in favor of drawing a blue ball?
P(draw a blue) = 10/15 = 2/3
P(not draw a blue) = 5/15 = 1/3
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Odds in favor of drawing a blue = (2/3)/(1/3) = 2:1
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what is the probability that it will have 2 red balls?
You are drawing 3 from 5 red and 10 blue.
P(exactly 2 red) = ?
# of ways to get 2 red = 5C2 = 10
# of ways to get 1 blue = 10C1 = 10
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# of ways to get 3 balls randomly: 15C3
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P(exactly 2 red) = (10*10)/15C3 = 100/455 = 20/91
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Cheers,
Stan H.