The Normal Distribution

What shape is a normal distribution curve?

• Half curve
• Round curve
• Bell curve
• Square curve

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CCSS.HSS.ID.A.2

CCSS.HSS.ID.A.3

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?

• 0.69

• 0.17

• 0.82

• -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?

• 0.34

• 0.28

• 0.4

• 0.65

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

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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%

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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

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CCSS.HSS.ID.A.4

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

• 100
• 25
• .5
• 1

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CCSS.HSS.ID.A.4

The distances male long jumpers for State College jump are approximately normal with a mean of 263 inches and a standard deviation of 14 inches.  
Suppose a male long jumper's jump ranked in the 75th percentile.  How long was his jump?

• 0.67 inch
• 263 inches
• 272.44 inches
• 277.25 inches

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CCSS.HSS.ID.A.2

CCSS.HSS.ID.A.4

CCSS.HSS.MD.A.3

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%

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CCSS.HSF-LE.A.1B

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 6 days or less?

• 68%
• 34%
• 16%
• 2.5%

Tags

CCSS.HSS.ID.A.4