<![CDATA[Math Is Fun Forum / Probability Random Variable with Central Limit Theorem]]> 2014-08-03T05:44:21Z FluxBB http://www.mathisfunforum.com/viewtopic.php?id=21294 <![CDATA[Re: Probability Random Variable with Central Limit Theorem]]> Hi bobbym,

Var(X) = E(x^2) - E(x)^2

and f(x) = 1 as this is uniform distribution from -1/2 to 1/2.

so:

Using Central Limit Theorem:

is the square root of the variance calculated above.
is the standard distribution.

Therefore P(-2 <= x <= 2) = 0.512

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http://www.mathisfunforum.com/profile.php?id=13139 2014-08-03T05:44:21Z http://www.mathisfunforum.com/viewtopic.php?pid=327087#p327087
<![CDATA[Re: Probability Random Variable with Central Limit Theorem]]> Hi;

I am getting:

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http://www.mathisfunforum.com/profile.php?id=33790 2014-08-02T08:53:02Z http://www.mathisfunforum.com/viewtopic.php?pid=327037#p327037
<![CDATA[Probability Random Variable with Central Limit Theorem]]> At a bank, the interest is calculated on 100 accounts and rounded up or down
to nearest cent. If it is assumed that the round-off error is uniformly distributed between
(-1/2, 1/2) and
the round-off errors are independent, find the probability that the sum
of the error does not exceed 2 cents in magnitude.

I dont understand how to calculate the variance for just one account. the answer for variance for just one account is 1/12.

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http://www.mathisfunforum.com/profile.php?id=13139 2014-08-01T10:53:11Z http://www.mathisfunforum.com/viewtopic.php?pid=326967#p326967