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How do you do this question?
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Zacken
22
Original post by fullmetal heart
How do you do this question?


We're not here to do your homework for you, please show some working or a smattering of your own thoughts concerning the question.
I'll start you off

Y~N (μ,σ2)

to find μ (mean) you do 1+2+3+44\frac{1+2+3+4}{4}
Reply 3
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Zacken
22
Original post by undercxver
I'll start you off

Y~N (μ,σ2)

to find μ (mean) you do 1+2+3+44\frac{1+2+3+4}{4}


Are you sure it's normally distributed?
Original post by Zacken
Are you sure it's normally distributed?


Discrete random variables. :facepalm:
I figured out the probabilities of the combinations and the sum of all the combinations, this meant that I could figure out the probabilities of getting a particular score. But I don't know what to do now?

UPDATE: I just remembered that I should use the formula for variance and then work out the standard deviation :P
(edited 8 years ago)
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Zacken
22
Original post by fullmetal heart


UPDATE: I just remembered that I should use the formula for variance and then work out the standard deviation :P


Yep standard deviation is just the square root of variance. :yep:
Original post by Zacken
Yep standard deviation is just the square root of variance. :yep:


Thanks, wow I can be thick sometimes, I literally just used that formula two questions ago
Reply 8
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Zacken
22
Original post by fullmetal heart
Thanks, wow I can be thick sometimes, I literally just used that formula two questions ago


No worries, glad you figured it out yourself!

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