Normal Curves & Z-scores Formative

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.

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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

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CCSS.HSS.ID.A.4

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 z-score represents.....

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

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CCSS.HSS.ID.A.4

If I have a positive z-score, I scored ABOVE or BELOW the mean?

• ABOVE

• BELOW

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CCSS.HSS.ID.A.4

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

• 5%
• 95%
• 2.5%
• 50%

Tags

CCSS.HSF-LE.A.1B

Adam's Z-score on a test is +2.5.  What does this mean?

• He'd better start studying.
• He did better than EVERYONE.
• He scored 2.5 standard deviations above the average.
• He did terrible.

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CCSS.HSS.ID.A.4

The distribution of heights of adult American men is approximately Normal with mean 69 inches and standard deviation 2.5 inches. Between what heights do the middle 95% of men fall? 

• 66.5-71.5
• 64-74
• 61.5-76.5
• 65-73

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CCSS.HSS.ID.A.4

The weights of adult male beagles are normally distributed, with a mean of 25 pounds and a standard deviation of 3 pounds. A beagle is randomly selected. Find the probability that the beagle’s weight is more than 29 pounds.

• 0.3694
• 0.3781
• 0.0912

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CCSS.HSS.ID.A.4

The weights of adult male beagles are normally distributed, with a mean of 25 pounds and a standard deviation of 3 pounds. A beagle is randomly selected. Find the probability that the beagle’s weight is between 23 and 26 pounds.

• 0.3694
• 0.3781
• 0.0912

Tags

CCSS.HSS.ID.A.4