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2 emergency probablity questions
Message posted by eva (via 171.159.64.10) on November 26, 2001 at 3:16 PM (ET)
Hi, thanks so much for this site. I have two emergency problems:
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Question 1 :
The probability of a computer being a Compaq is 15%. A company has 26 computers, what is the probability that 7 are Compaqs?
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Question 2 :
A couple has 4 children. The grandparents have propsed to the parents :
If all four children go to college, the couple will receive $10,000.
If three children go to college, the couple will receive $5,000.
If two of the cildren go to college, they will receive $2,000.
If one goes to college, they recieve $1,000.
If none go, they receive nothing.
Assuming the probability of each child going to college is 0.5, what is the parent's monetary expectation?
READERS RESPOND:
(In chronological order. Most recent at the bottom.)
Re: 2 emergency probablity questions
Message posted by Jack Tomsky (via 208.249.113.130) on November 27, 2001 at 5:34 PM (ET)
I. In reality, most companies buy their computers in bulk. So the probability of zero Compaqs is 85% and the probability of 26 Compaqs is 15%. The probability of any other number of Compaqs is zero. Obviously the question wants you to assume that the brand of computer at each desk is random. In that case, use the binomial distribution.
II. Calculate the binomial probabilities of the number of children going to college, multiply each by the inheritance, and add them up.
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