Question 142014
Suppose that Math 103 scores are normally distributed and they have a mean of 80 and a standard deviation of 6.
A) Find the Math 103 Score two standard deviations above the mean.
The z-score of a data value that is 2 standard deviations above the mean is +2.
Use the formula z(x) = (x-u)/sigma to solve for x:
2 = (x-80)/6
12 = x-80
x = 92
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B)What percent of all scores is greater than 92?
The z-score of 92 is +2. You want P(z > 2)
Use your z-chart to find the answer which is 0.0228 or 2.28%
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Cheers,
Stan H.