SOLUTION: For a sample with a mean of M = 50 and a standard deviation of s = 10, a z-score of z = +2.00 corresponds to X = 70. True False

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Question 1117263: For a sample with a mean of M = 50 and a standard deviation of s = 10, a z-score of z = +2.00 corresponds to X = 70.
True
False

Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
formula for z-score is:

z = (x - m) / s

x is the score you are comparing to the mean.
m is the mean.
s is the standard deviation / standard error

when z = 2 and m = 50 and s = 10, you get:

2 = (x - 50) / 10

solve for x to get x = 20 + 50 = 70

therefore true.

the z-score tells you the number of standard deviations / standard errors you are above or below the mean.

the z-score of 2 tells you you are 2 standard deviations / standard errors you are above the mean.

2 * 10 = 20 + 50 = 70

standard error is involved with sample means which you will learn about later if you haven't already.

so, until then, the formula is z = (x - m) / s, where s is the standard deviation.