Z-scores and emperical rule

Find the z-score value corresponding if the location is below the mean by 2 standard deviations

• +2.00

• -2.00

• +1.25

• -1.00

Tags

CCSS.HSS.ID.A.4

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

Tags

CCSS.HSS.ID.A.4

A 12 oz can of soda has a mean volume of 12 oz, with a standard deviation of .25 oz. How common are cans with less than 11.5 oz of soda? Calculate the probability.

• 2.5%
• .15%
• 2.35%
• 2.25%

Tags

CCSS.HSS.ID.A.4

At a local high school, GPA's are normally distributed with a mean of 2.9 and standard deviation of 0.6. What percentage of students at the high school have a GPA between 2.3 and 3.5?

• 68%
• 99.7%
• 95%
• 84%

Tags

CCSS.HSS.ID.A.4

The mean life of a tire is 30,000 km. The standard deviation is 2000 km.

Then, 68% of all tires will have a life between ___________ km and __________ km.

•  28,000 km and 32,000 km.
• 24,000 km and 34,000 km.
• 26,000 km and 34,000 km.
• 27,000 km and 31,000 km.

Tags

CCSS.HSS.ID.A.4

At a local high school, GPA's are normally distributed with a mean of 2.9 and standard deviation of 0.6. What is the GPA of the highest 2.5% of the students?

• 4.1 
• 4.1 or higher
• 4.7
• 4.5 or higher

challenge:  The mean June midday temperature in Desertville is 36°C and the standard deviation is 3°C
Assuming this data is normally distributed, how many days in June would you expect the midday temperature to be between 39°C and 42°C?

• 3
• 4
• 7
• 14

Find the Z-score.

Mean = 22

Standard Deviation: 3.1

x = 29

• 2.26

• 16.45

• -2.26

• 1.26

Tags

CCSS.HSS.ID.A.4

Find the mean.

Z-score = -1.25

Standard Deviation: 4

x = 11

• 16

• 6

• 18

• 21

Tags

CCSS.HSS.ID.A.4

CCSS.HSS.MD.A.2

CCSS.HSS.MD.A.3

In a normal distribution, what percent of the values lie within one standard deviation of the mean?

(from z = -1 to z = 1)

• 13.5%

• 34%

• 95%

• 68%

Tags

CCSS.HSS.ID.A.4