# statistics

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Find the value of zα/2 to construct a confidence interval with level:
a. 95%
b. 98%

• statistics -

Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportions (.025 & .01, respectively) that relate to the Z scores.

95% interval = mean ± 1.96 SD, so Z = 1.96.

You do the second one.

• statistics -

I got it! the second one is Z = 2.326
Thanks!!! :)

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