Empirical Rule
Z-Scores
Probably Yes...
Probably No!
How do I stand?
Symbolic Mysteries
100

The percentage of data located within 1 standard deviation of the mean.

What is 68%

100

The z-score corresponding to an SAT score of 630 when the mean score is 500 and the standard deviation is 100.

What is 1.3

100

The probability of randomly selecting a member of a normally distributed population with a value less than the mean of the population.

What is .5

100
My percentile if I scored a 730 on the math portion on the SATs when the mean is 518 and the standard deviation is 115.
What is the 97th percentile
100
The greek symbol used to represent standard deviation.
What is sigma (lower case) ?
200

The percentage of data located within 2 standard deviations of the mean.

What is 95%

200

The sign of the z-score of any data point that falls BELOW the mean.

What is a negative z score?

200

US men in the age group of 20-29 have heights that are normally distributed with a mean of 69.6 inches and a standard deviation of 3.0 inches. This is the probability of randomly selecting a man in this age group whose height is more than 72 inches.

What is .21

200
My percentile if I scored a 620 on the critical reading portion on the SATs when the mean is 503 and the standard deviation is 113.
What is the 85th percentile
200
the symbol for variance.
what is sigma squared?
300

The percent of data located within 3 standard deviations of the mean.

What is 99.7%?

300
The z score of a data point that is equal to the mean of the data.
What is 0?
300
US men in the age group of 20-29 have heights that are normally distributed with a mean of 69.6 inches and a standard deviation of 3.0 inches. This is the probability of randomly selecting a man in this age group whose height is between 66 and 72 inches.
What is .67
300
The score on the math portion on the SATs that represents the 90th percentile when the mean is 518 and the standard deviation is 115.
What is 665
300
The z score tells you how many of these a data point is from the mean.
What is standard deviation?
400

The percent of the data that lies outside of 1 standard deviation from the mean?

What is 32%?

400
The area under the standard normal curve that is to the left of a z-score of 2.
What is .84
400
The weights of adult male beagles are normally distributed, with a mean of 25 pounds and a standard deviation of 3 pounds. This is the probability of randomly selected an adult male beagle whose weight is less than 23 pounds.
What is .25
400
The cutoff score on the math portion on the SATs that separates the top 20% when the mean is 518 and the standard deviation is 115.
What is 615
400
The three measures of dispersion.
What are range, variance and standard deviation?
500

The percentage of data located between the mean and 1 standard deviation above the mean.

What is 34%?

500
The area under the standard normal curve between the z-scores of -2 and 1.
What is .815
500
The weights of adult male beagles are normally distributed, with a mean of 25 pounds and a standard deviation of 3 pounds. This is the probability of randomly selected an adult male beagle whose weight is less than 22 pounds or greater than 28 pounds.
What is .32
500
The z-score that corresponds to the cumulative area on the left of 0.3520.
What is -.38
500
Data for which the mode < Median < Mean.
What is right skewed data?
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