4/15 Normal Distribution, Z-Score Practice

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.

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

Find the area under the standard normal curve to the left if z = -2.67.

• 0.38%

• 99.62%

• 65.32%

• 12.32%

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CCSS.HSS.ID.A.4

The mean temperature in Glens Falls for the month of February is 23 degrees with a standard deviation of 4.2 degrees. What is the z-score for a temperature of 17 degrees?

• 1

• 1.43

• -1.43

• 11.5

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CCSS.HSS.ID.A.4

Joanne's Z-score is -1.5. What does this mean?

• She didn't take the test yet.

• She scored 1.5 standard deviations below the average.

• She did better than most people.

• No clue

Chris took a spatial abilities test (mean = 80, std. dev. = 8).

Chris scored a 94.

What percent of individuals would score less than Chris?

• 26.8%

• 96%

• 65.1%

• 4%

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CCSS.HSS.ID.A.4

Fernando is 60 inches tall. The average height for his age and gender is 68 with a standard deviation of 10 inches.

What percent of his peers are shorter than him?

• 46.81%

• 8%

• 78.81%

• 21.19%

Tags

CCSS.HSS.ID.A.4

Calculate the z score if the mean is 75, your score is 90 and σ is 4.5

• -3.33

• 3.33

• 1.77

• 2.1

The mean GPA of students in a course at UCDavis is 3.2 with a standard deviation of 0.2.

What percent of students in the course have a GPA above 3.5?

• 93.32%

• 47.5%

• 23.25%

• 6.68%

Tags

CCSS.HSF-LE.A.1B

The average age of a group of fans at a hockey game is 34 years with a standard deviation of 8 years.

What percent of fans are older than 28 years old?

• 22.66%

• 16.66%

• 77.34%

• 2.28%

Tags

CCSS.HSS.ID.A.4