# stats

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A set of 50 data values has a mean of 30 and a variance of 4.
I. Find the standard score (z) for a data value = 26.
II. Find the probability of a data value < 26.

I think the first part is z=(26-30)/4 = -4/4 = -1. I am not sure how to go about the second problem. I could use any help. Thanks

• stats -

1. Z =( score-mean)/SD

Variance = SD squared

2. Same equation, but find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion related to Z.

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