Imperical Rule
Zombie 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

For a certain type of computers, the length of time between charges of the battery is normally distributed with a mean of 50 hours and a standard deviation of 15 hours. John owns one of these computers and wants to know the probability that the length of time will be between 50 and 70 hours.

What is 0.4082?

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 diviation 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

A large group of students took a test in Physics and the final grades have a mean of 70 and a standard deviation of 10. If we can approximate the distribution of these grades by a normal distribution, what percent of the students scored higher than 80?

What is 15.87%?

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

Six hundred mathematics students sat for an exam. There marks were normally distributed with a mean of 63 and a standard deviation of 8. How many students would you have expected to score more than 69%? 

What is 96 students. 

500
Data for which the mode < Median < Mean.
What is right skewed data?
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