Normal Distributions Unit Review

The z-score represents.....

• the amount of standard deviations a data point is above or below the mean.
• the percentile the data point is above or below the mean.
• the amount of standard deviations a data point is above or below the median.
• the percent the data point is above or below the mean.

If we say that "a" is the b^th percentile, that means...

• b% of a data set is less than or equal to "a."
• b% of a data set is greater than or equal to "a."
• a% of a data set is less than or equal to "b."
• a% of a data set is greater than or equal to "b."

Tags

CCSS.6.SP.B.5C

What shape is a normal distribution curve?

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

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

• 100
• 25
• .5
• 1

Tags

CCSS.7.SP.C.7A

Who discovered the Normal Distribution?

• Gauss
• Chebychev
• Poisson
• Pearson

The average waist size for teenage males is 29 inches with a standard deviation of 2 inches.  What is the z-score of a teenage male with a 33 inch waist?

• 2.00
• 1.00
• -2.00
• -1.00

Tags

CCSS.HSS.ID.A.4

The mean life of a tire is 30,000 km. The standard deviation is 2000 km. The lifespan of these tires approximates a normal distribution.

Therefore, around 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 shelf life of a particular dairy product approximates a normal distribution 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%

Tags

CCSS.HSS.ID.A.4

Pat and Chris both took a spatial abilities test (mean = 80, std. dev. = 8).  Pat scores a 76 and Chris scored a 94. If the distribution of scores is approximately normal, what percent of individuals would score between Pat and Chris? 

• 26.8%
• 96%
• 65.1%
• 4%

Tags

CCSS.HSS.ID.A.4

In a factory, the weight of the concrete poured into a mold by a machine approximates a normal distribution with a mean of 1150 pounds and a standard deviation of 22 pounds. Approximately 95% of molds filled by this machine will hold weights in what interval? 

• 1084 to 1216 pounds 
• 1106 to 1150 pounds 
• 1106 to 1194 pounds 
• 1128 to 1172 pounds

Tags

CCSS.HSS.ID.A.4