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September 12, 2025, 07:38:15 am
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Author Topic: Probability Help  (Read 1290 times)  Share 

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GiPhat

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Probability Help
« on: March 27, 2010, 12:37:02 pm »
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Hi guys, just needed some proving help: Why is it the in a standard normal distribution, where X has a mean of mew and standard deviation of sigma, That the expected value of Z is 0 and the variance of Z is 1?
Please help out
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kyzoo

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Re: Probability Help
« Reply #1 on: March 27, 2010, 01:01:30 pm »
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That's the definition of the standard normal distribution

Mean = Expected value = 0
Standard Deviation = 1
Variance = (Standard Deviation)^2 = 1
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2009
~ Methods (Non-CAS) [48 --> 49.4]

2010
~ Spesh [50 --> 51.6]
~ Physics [50 --> 50]
~ Chem [43 --> 46.5]
~ English [46 --> 46.2]
~ UMEP Maths [5.0]

2010 ATAR: 99.90
Aggregate 206.8

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GiPhat

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Re: Probability Help
« Reply #2 on: March 27, 2010, 01:20:27 pm »
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yeah, but i was wondering how do we prove that using just a generic random variable X and get that result
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kyzoo

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Re: Probability Help
« Reply #3 on: March 27, 2010, 02:30:13 pm »
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You don't? Because that's the fundamental definition.

It's like saying, prove that "ab" equals "a x b"
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2009
~ Methods (Non-CAS) [48 --> 49.4]

2010
~ Spesh [50 --> 51.6]
~ Physics [50 --> 50]
~ Chem [43 --> 46.5]
~ English [46 --> 46.2]
~ UMEP Maths [5.0]

2010 ATAR: 99.90
Aggregate 206.8

NOTE: PLEASE CONTACT ME ON EMAIL - [email protected] if you are looking for a swift reply.

GiPhat

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Re: Probability Help
« Reply #4 on: March 27, 2010, 03:33:19 pm »
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uhh, ok but it was part of my assignment so i think you should be able to prove it...i'm so confused... :-\
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