Normal Distribution and S.D.

Students pass a test if they score 50% or more.

The marks of a large number of students were sampled and the mean and standard deviation were calculated as 42% and 8% respectively.

Assuming this data is normally distributed, what percentage of students pass the test?

• 5%

• 16%

• 24%

• 32%

68% of the marks in a test are between 51 and 64

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

Tags

CCSS.HSS.ID.A.4

The normal curve is symmetrical about the mean.

• True
• False

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

• 68%

• 95%

• 99.8%

• 50%

1.  Which best describes the shaded part of this normal distribution graph?  

• All data that is one or higher.
• All data that is one or more standard deviations above the mean.
• All data that is between 1 and 3.
• All data that is above the mean.

Tags

CCSS.HSS.ID.A.4

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

• 68%

• 95%

• 99.8%

• 50%

Tags

CCSS.HSS.ID.A.4

CCSS.HSS.MD.A.1

CCSS.HSS.MD.A.3

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

• 68%

• 95%

• 99.8%

• 50%

Tags

CCSS.HSS.ID.A.1

CCSS.HSS.ID.A.4

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

• 68%

• 32%

• 16%

• 50%

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

The average waist size for teenage males is 29 inches with a standard deviation of 2 inches. 
If waist sizes are normally distributed, determine the z-score of a teenage male with a 33 inch waist.  

• 2
• 1
• -2
• -1

Tags

CCSS.HSS.ID.A.4