Empirical Rule

Find the z-scores value corresponding if the location is above the mean by 1/2 standard deviations

• -0.50

• +1.00

• +0.50

• -1.00

If Gonzalo's score is 87, the class average is 82, and the SD is 4, what is Gonzalo's Z-score?

• -1.25

• +1.25

• +1.20

• +1.02

This data is normally distributed. What percent of the data is in the shaded region?

• 68%

• 95%

• 99.8%

• 50%

According to the normal distribution, what percent of the population has an IQ between 70 -115

• 68%

• 81.5%

• 95%

• 47.5%

What percentage of the data falls within three standard deviations from the mean?

• 99.7%

• 92%

• 68%

• 65%

Assuming this data is normally distributed, what are the mean and standard deviation?

• Mean = 57 S.D. = 6.5

• Mean = 57 S.D. = 7

• Mean = 57.5 S.D. = 6.5

• Mean = 57.5 S.D. = 13

Assuming this data is normally distributed, what are the mean and standard deviation?

• Mean = 66 kg S.D. = 7 kg

• Mean = 76 kg S.D. = 7 kg

• Mean = 86 kg S.D. = 7 kg

• Mean = 76 kg S.D. = 14 kg

According to the empirical rule, what percentage of data falls within 1 standard deviation?

• 25%

• 68%

• 95%

• 99.7%

The mean GPA of students in a course at UCDavis is 3.2 with a standard deviation of 0.3. What percent of students in the course have a GPA between 2.9 and 3.8?

• 81.5%

• 47.5%

• 68%

• 95%

The shelf life of a particular dairy product is normally distributed with a mean of 12 days and a standard deviation of 3 days.

About what percent of the products last between 12 and 15 days?

• 68%

• 34%

• 16%

• 2.5%