Question

For a particular group of scores, M=20 and SD=5. Give the Z score for (a) 30 (b) 15 (c) 20 and (d) 22.5.

a) (a) 2, (b) -1, (c) 0, (d) 0.5
b) (a) 6, (b) -1, (c) 0, (d) 0.5
c) (a) 2, (b) -1, (c) 1, (d) 0.5
d) (a) 1, (b) -1, (c) 0, (d) 0.5

Answer 1

The z-score is a measure of how many standard deviations a particular value is from the mean of a data set. To calculate the z-score, we use the formula: z = (x - M) / SD.

Step-by-step explanation:

The z-score is a measure of how many standard deviations a particular value is from the mean of a data set. To calculate the z-score, we use the formula: z = (x - M) / SD, where x is the value, M is the mean, and SD is the standard deviation.

For the given data set with M = 20 and SD = 5:

• For a value of 30, the z-score would be (30 - 20) / 5 = 2.
• For a value of 15, the z-score would be (15 - 20) / 5 = -1.
• For a value of 20, the z-score would be (20 - 20) / 5 = 0.
• For a value of 22.5, the z-score would be (22.5 - 20) / 5 = 0.5.