Question

17. A set of values has a mean of 102 and a standard deviation of 12. Find

the z-score of the value 135.

Answer 1

z = 2.75

Explanation:

The formula used for z-score is:

`z=(x-\mu)/(\sigma)`

where,
`\mu` is the population mean

`\sigma` is the standard deviation

and x is the value of observation.

Here, x = 135,
`\mu` = 102 and,
`\sigma` = 12

Putting all these values in formula of z-score. We get,

`z=(135-102)/(12)`

⇒ z = 2.75

It mean that values have score 2.75 standard deviations above the mean.