Question 1001039
A pet store has seven puppies, including four poodles, two terriers, and one retriever. 
If Rebecka and Aaron, in that order, each select one puppy at random, with replacement ( they may both select the same one), find the probability of each event. 
14) Rebecka selects a retriever AND Aaron selects a terrier
Ans:P(retriever AND terrier) = P(retriever)*P(terrier) = (1/7)(2/7) = 1/7
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16) both select a retriever
Ans: P(retriever AND retriever) = [P(retriever)]^2 = (1/7)^2 = 1/14
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So...the next one is a follow up question with the same dogs 
Suppose two puppies are selected as earlier, but this time without replacement (Rebecka and Aaron cannot both select the same puppy). Find the probability of each event.
[A pet store has seven puppies, including four poodles, 
two terriers, and one retriever.]
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17) both select a poodle
P(poodle AND poodle) = (4/7)(3/6) = 12/42 = 6/21 = 2/7
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18) Aaron selects a terrier, given Rebecka selects a poodle
P(terrier | poodle) = (2/6)(4/7) = 4/21
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19) Aaron selects a retriever, given Rebecka selects a poodle
P(retriever |poodle) = (1/6)(4/7) = 2/21
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20) Rebecka selects a retriever
Ans: 1/7
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Cheers,
Stan H.
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