Thread: [SOLVED] Normal Distrubtion Question
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Old April 16th, 2008, 12:21 AM
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Default [SOLVED] Normal Distrubtion Question
Question:
Given that X \sim N(44,25), find t correct to 2 decimal places when
P(X \geq t)=0.7704

Attempt:

= P(X \geq t)=0.7704

\mu = 44 , \sigma^2 = 25, \sigma= 5

= P(\frac{X-\mu }{ \sigma } \geq \frac{X-44}{ 5})

1 - \frac{X-44}{5} = 0.7704

1 - 0.7704 = \frac{X-44}{5}

0.26 = \frac{X-44}{5}

1.3 = X - 44

X = 45.3

Where did I go wrong?
Last edited by looi76; April 16th, 2008 at 05:46 AM.
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