# Confidence Intervals and corresponding z-scores

A cutoff score of 79 has been established for a sample of scores in which the mean is 65. If the corresponding z-score is 1.4 and the scores are normally distributed, what is the standard deviation?

© BrainMass Inc. brainmass.com June 3, 2020, 4:57 pm ad1c9bdddfhttps://brainmass.com/statistics/confidence-interval/confidence-intervals-corresponding-z-scores-9611

#### Solution Preview

Solution. Assume that the standard deviation is x, by the hypothesis, we know that

|79-65|/x=1.4, so x=10

that is,

the ...

#### Solution Summary

The solution answers the question(s) below.

$2.19