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HSC Stuff => HSC Maths Stuff => HSC Subjects + Help => HSC Mathematics Extension 1 => Topic started by: frog0101 on November 02, 2017, 06:08:02 pm

Title: Probability Question
Post by: frog0101 on November 02, 2017, 06:08:02 pm: Hi, I found this question, however it doesn't come with answers. I got 3C0 (.72)^3, is this correct??
A given school in a certain state has 3 Mathematics teachers. The probability in the state that a mathematics teachers is female is 0.4.
In the same state, the probability that a mathematics teachers (male or female) is a graduate is 0.7. What is the probability that in the given school none of the three mathematics teachers is a female graduate.

Thanks :)
Title: Re: Probability Question
Post by: jamonwindeyer on November 02, 2017, 08:00:35 pm: Hey!! So yep, the probability they are NOT a female graduate is:

$P\left(\text{Not a Female Graduate}\right)=1-0.7\times0.4=0.72$

And we need three of those, so yep that's correct ;D

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