Finding z-scores

A z-score indicates how many standard deviations an element is from the mean of a distribution.

The formula for finding z-scores is $$z = \frac{x - \mu}{\sigma}$$ where x is the value, \mu is the mean, and \sigma is the standard deviation.

The z-score will be positive.

The z-score will be negative.

A z-score of 0 indicates that the value is exactly at the mean.

A z-score of 1.5 means the value is 1.5 standard deviations above the mean.

A z-score of -1.2 means the value is 1.2 standard deviations below the mean.

The mean is 21 and the standard deviation is 5.

The z-score is 1.40.

The z-score is -0.70.