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## #1 2012-11-24 11:25:19

infinitebrain
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### Probability Question

Six boys and twelve girls are in a senior class.Half the boys and 25% of the girls wear glasses.What is the chosen probability that a student chosen randomly is a boy,wears glasses,or both? I know the answer is 50%, but could someone could explain to me clearly how you get that answer? Thanks!

The best thing about life is you don't know what to expect

## #2 2012-11-24 13:19:58

Agnishom
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### Re: Probability Question

Probability that the chosen one is a boy =

Probability that the chosen one wears glasses =

Probability that the chosen one is both a boy and wears glasses = (Probability of being a boy) * (Probability of a boy to wear glasses) =

Last edited by Agnishom (2012-11-24 13:22:47)

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
'The whole person changes, why can't a habit?' -Alokananda

## #3 2012-11-24 13:35:03

infinitebrain
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### Re: Probability Question

Thank you Agnishom!
Sorry, I went back to look at the documents and it said A is correct, which is 16 2/3%!

The best thing about life is you don't know what to expect

## #4 2012-11-24 13:41:15

Agnishom
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### Re: Probability Question

You are Welcome, @infinitebrain

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
'The whole person changes, why can't a habit?' -Alokananda