Worksheetsz-score (Standard Score), Quartiles
Total questions: 12
Worksheet time: 2hrs 5mins
Adam's z-score on a test is 2.5. What does this mean?
He scored 2.5 standard deviations above the mean.
She scored 1.5 standard deviations below the mean.
What is one of the correct formulas for finding z-scores?
z=σx−μ
z=σμ−x
Sx=σx−μ
If Gonzalo's score is 87, the class mean is 82, and the s = 4, what is Gonzalo's z-score?
What is the z-score (standard score) for Tina if she got a 31 on the ACT, the mean was 23 and the standard deviation was 4?
0.2
2.0
What is the standard score for Paula if she got 1400 on the SAT, the mean was 1100 and the standard deviation was 275?
1.09
1.90
So if Tina's Z-score is 2.0 and Paula's Z-score is 1.09, who performed better?
Tina's performance is farther away from and above the mean, so she did better.
Adam's Z-score on a test is 2.50. What does this mean?
Adam's score has a 2.5% chance of being better than any other randomly selected score.
Adam's test score was better than 25% of his peers.
He scored 2.5 standard deviations above the average.
He did terrible.
The 50th percentile is also known as the _______________.
median
mean
mode
best percentile
In a factory, the weight of the concrete poured into a mold by a machine follows a normal distribution with a mean of 1150 pounds and a standard deviation of 22 pounds. What weight falls at the 50th percentile?
1106 pounds
1128 pounds
1150 pounds
1172 pounds
