Question

When given a raw score, explain how to use the normal curve to compare that score to the population.

Answer 1

Assuming you know the mean (mu) and the standard deviation (sigma), you would use the raw score (x) to get the z score through this formula

z = (x-mu)/sigma

If you get a positive z value, then the raw score is above the mean. If z is negative, then the raw score is below the mean.

The absolute value of z tells us how far away from the mean we are in terms of standard deviation.

Eg: z = -3 leads to |z| = |-3| = 3, so we're 3 standard deviations below the mean.