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**infinitebrain****Member**- Registered: 2008-07-01
- Posts: 153

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

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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 (2012-11-23 14:22:47)*

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'

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**infinitebrain****Member**- Registered: 2008-07-01
- Posts: 153

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

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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'

'But our love is like the wind. I can't see it but I can feel it.' -A Walk to remember

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