Normal Distribution

In a survey of men in the United States (ages 20-29), the mean height was 69.6 inches with a standard deviation of 3.0 inches. Find the minimum height in the top 22%.

• 69.37 in

• 67.58 in

• 71.91 in

The 40 yards sprint times for a soccer team are found to be normally distributed with a mean of 5.2 seconds and a standard deviation of 0.3 seconds.  What is the z-score for a player who runs a time of 5.6 seconds?

• -1.33
• 1.33
• 0.88
• 1.02

Tags

CCSS.HSS.ID.A.4

The 40 yards sprint times for a soccer team are found to be normally distributed with a mean of 5.2 seconds and a standard deviation of 0.3 seconds.  What is the z-score for a player who runs a time of 4.6 seconds?

• 0.83
• 1.07
• -2
• -1.07

Tags

CCSS.HSS.ID.A.4

The mean number of accidents a week at a company is 6.4 with a standard deviation of 1.5. What proportion of weeks would you expect to have less than 5 accidents?

• 0.6915

• 0.1753

• 0.8238

• -0.93

The mean number of accidents a week at a company is 6.4 with a standard deviation of 1.5.  What proportion of weeks would you expect to have more than 7 accidents?

• 0.3446
• 0.2856
• 0.4
• 0.6554

Tags

CCSS.HSS.ID.A.4

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%

Tags

CCSS.HSS.ID.A.4

Between what two standard deviations of a normal distribution contain 68% of the data?

• one below and one above
• two below and two above
• two below and zero
• zero and two above

Tags

CCSS.HSS.ID.A.4

The average waist size for teenage males is 29 inches with a standard deviation of 1.4 inch. 
If waist sizes are normally distributed, estimate the proportion of teenagers who will have waist   sizes greater than 31 inches?

• 92.4%
• 10.5%
• 16%
• 7.6%

Tags

CCSS.HSS.ID.A.4

The scoring of modern IQ is such that Intelligence Quotients (IQs) have a normal distribution of μ= 100 and 𝞂 = 15.

Mensa International is a non-profit organization that accepts only people with IQ score within the top 2%. What level of IQ qualifies one to be a member of Mensa?

• 115
• 130.75
• 145
• 120

Tags

CCSS.HSS.ID.A.4

What is the the total area under the standard normal distribution curve?

• 100
• 25
• .5
• 1

Tags

CCSS.HSS.ID.A.4