IQ scores have a mean of 100 and a standard deviation of 15. Kate has an IQ of 121.
What is the difference between Kate's IQ and the mean?
Convert Kate's IQ score to a z score:

Question

IQ scores have a mean of 100 and a standard deviation of 15. Kate has an IQ of 121. 
What is the difference between Kate's IQ and the mean?  
Convert Kate's IQ score to a z score:

jim_thompson5910 · Answer

What is the difference between Kate's IQ and the mean?

jim_thompson5910 · Answer

I'm sure you know this. Difference means subtraction.

anonymous · Answer

21 I miss read the question hah

jim_thompson5910 · Answer

21 is the difference, yes

jim_thompson5910 · Answer

to get the z-score, you divide the difference by the standard deviation

anonymous · Answer

I always forget that for some reason

jim_thompson5910 · Answer

the z-score formula is

$$\Large z = \frac{x - \mu}{\sigma}$$

$\Large \mu$ (myoo) is the mean

$\Large \sigma$ (sigma) is the standard deviation