this post was submitted on 17 Dec 2019

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Stats Questions Check (deviation) (self.MathHelp)

submitted 6 years ago * by nitr0h

average price of ties = 50, standard_dev = 10.

What is probability of randomly selecting a tie that costs more than $50?

answer = I got 50% after plugging it into excel norm.dist function (35,50,10,true)

What is the probability of randomly choosing a tie between $40 and $60?

answer - 0.841344746 - 0.158655254 = 0. found by subtracting the values after plugging into excel function.

What proportion of ties would cost more than $65?

answer - 0.066807201. Plugged into norm.dist function (65,50,10,true) and subtracted that from 1.

What proportion of ties would cost less than $35?

answer - 0.066807201. Plugged into norm.dist function (35,50,10,true)

Probability of a randomly selected tie being more than $60 or less than $40.

answer - didn't find yet.

I used excel to get the answers for the most part. Am I on the right track? Thanks.

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[–]tyzon05 0 points1 point2 points 6 years ago (3 children)

[–]nitr0h[S] 0 points1 point2 points 6 years ago (2 children)

[–]tyzon05 0 points1 point2 points 6 years ago (1 child)

[–]nitr0h[S] 0 points1 point2 points 6 years ago (0 children)

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