SOLUTION: Suppose a furniture store found that 20% of the people who enter buy something. Three potential customers walk in. Y means a sale, and N means no sale. 1. The probability of a

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Question 1028823: Suppose a furniture store found that 20% of the people who enter buy something. Three potential customers walk in. Y means a sale, and N means no sale.

1. The probability of at least one sale out of three customers is?
A) .512 B) .488 C) .6 D) .841
2. The probability of exactly one sale out three customers is?
A) .2 B) .141 C) .8 D) .384 E) .128
Found 2 solutions by Fombitz, stanbon:
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Probability of selling to none of the three.
P%28NNN%29=0.8%280.8%29%280.8%29=0.512
So the complement is selling to at least one.
P=1-P%28NNN%29
P=1-0.512
P=0.488
.
.
.
It can happen three ways
P(NNY)
P(NYN)
P(YNN)
All three probabilities are identical,
P=0.8%280.8%29%280.2%29=0.128
So for three of them,
P%281Y%29=0.384

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Suppose a furniture store found that 20% of the people who enter buy something. Three potential customers walk in. Y means a sale, and N means no sale.
1. The probability of at least one sale out of three
P(>=1) = 1 - P(none) = 1-(0.8)^3 = 0.488
A) .512 B) .488 C) .6 D) .841
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2. The probability of exactly one sale out three customers is?
A) .2 B) .141 C) .8 D) .384 E) .128
P(x = 1) = 3C1*0.2*0.8^2 = 3*0.2*0.64 = binompdf(3,0.2,1) = 0.384
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Cheers,
Stan H.
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