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How do you determine the probability of p(x>108) with the standard deviation of 8, and the mean of 100? Z=1

nala said:

How do you determine the probability of p(x>108) with the standard deviation of 8, and the mean of 100? Z=1

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Start a new thread with new problem.

What does that Z = 1 mean?

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nala said:

How do you determine the probability of p(x>108) with the standard deviation of 8, and the mean of 100? Z=1

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I take it that z is the "standardized variable \(\displaystyle \frac{x- \mu}{\sigma}\) which here is \(\displaystyle \frac{108- 100}{8}= 1\).

Look up the probability \(\displaystyle P(z\le 1)\) in a table of the normal distribution (I'm guessing this is a normal distribution problem- you should have said that). Some tables give \(\displaystyle P(-\infty< z< z_0)\). If that is the case for your table \(\displaystyle P(z\ge 1)= 1- P(-\infty< z< 1)\). Others give \(\displaystyle P(0< z< z_0)\) for positive \(\displaystyle z_0\). If that is the case for your table \(\displaystyle P(z\ge 1)= \frac{1}{2}- P(0< z< z_0)\).