# statistics

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standard deviation 1.2. Random selection of 70 found a mean of 5.2. I have to find a 87% confidence level given this info?

• statistics -

Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion/probability ([1-.87]/2) and its Z score.

87% = mean ± Z(SD)

Fill in the values and calculate.

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