Unit 12 Test Review

An achievement test given to 4th graders had a mean score of 360 and a standard deviation of 15. If Tom’s z-score was -0.60, what did he score on the test?

• 351

• 360

• 369

• 345

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CCSS.HSS.ID.A.4

The data below represents the ages of the fifteen recruits in the police academy. The data has a mean of 27 and a standard deviation of 3.8, rounded to the nearest tenth. How many of these data points have a z-score less than -0.4? {21, 22, 24, 24, 25, 25, 25, 26, 27, 28, 29, 30, 32, 32, 35}

• 2

• 3

• 4

• 5

Statistical information for a dataset is given below: - The mean of the data set is 74. - The standard deviation of the data set is 3. - The z-score for a data point in the set is 1.5. In which interval does this data point fall?

• 65 ≤ x ≤ 70

• 71 ≤ x ≤ 75

• 76 ≤ x ≤ 80

• 81 ≤ x ≤ 85

Given a normally distributed data set, approximately what percentage of the data will fall within one standard deviation of the mean?

• 68%

• 90%

• 95%

• 99%

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CCSS.HSS.ID.A.4

The grades from an Algebra Midterm were as follows: {60, 64, 75, 78, 83, 86, 91, 95, 98, 100} a) How many grades fall within one standard deviation of the mean?

• 6

• 7

• 8

• 9

The grades from an Algebra Midterm were as follows: {60, 64, 75, 78, 83, 86, 91, 95, 98, 100} b) How many grades fall within two standard deviations of the mean?

• 7

• 8

• 9

• 10

The grades from an Algebra Midterm were as follows: {60, 64, 75, 78, 83, 86, 91, 95, 98, 100} c) How many grades have a z-score less than 0.3?

• 2

• 4

• 6

• 8

The mean price of regular grade gasoline amongst several gas stations in a city is $3.52 with a standard deviation of 0.12. If the gas station closest to Mark’s house charges $3.59 for regular gas, what is its z-score? Round to the nearest tenth.

• 0.6

• 0.5

• 0.8

• 0.7

• the data point in question

• the mean of the data set

• the standard deviation of the data set

• the mode

Tags

CCSS.HSS.ID.A.4

Suppose a data set is represented by a normal distribution with a mean of 125 and a standard deviation of 7.

What data value is 2 standard deviations above the mean?

• 125

• 132

• 139

• 750

Tags

CCSS.HSS.ID.A.4