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#1 2012-04-25 06:05:19

mom
Member
Registered: 2012-04-25
Posts: 94

Probability

I forgot how to work this out. Can you please help?

In a region, 70% of the population have brown eyes. If 14 people are rondomly selected, find the probability that at least 12 of them have brown eyes. Is it unusual to randomly select 14 people and find that at least 12 of them have brown eyes? Why or why not?

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#2 2012-04-25 06:16:00

Bob
Administrator
Registered: 2010-06-20
Posts: 10,053

Re: Probability

hi mom,

Welcome to the forum!

This is a binomial situation.  n = 14 and p(brown) = 0.7

Finf P(12), P(13) and P(14) and add them.

If this probablitity is very small you can declare it is unusual.  I suggest you say this if P(answer) < 0.05

Bob


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

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#3 2012-04-25 06:23:09

mom
Member
Registered: 2012-04-25
Posts: 94

Re: Probability

Thank you.

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#4 2012-04-25 06:49:01

Bob
Administrator
Registered: 2010-06-20
Posts: 10,053

Re: Probability

You're welcome.  smile

Bob


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

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