The normal distribution (68–95–99.7 rule)

Question 1

A variable is normally distributed with mean 143 and standard deviation 8. About what percentage of values lie between 135 and 151?

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Question 2

Scores have mean 49 and standard deviation 12. What is the z-score of 73?

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Question 3

A variable is normally distributed with mean 164 and standard deviation 10. About what percentage of values lie between 154 and 174?

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Question 4

Scores have mean 75 and standard deviation 8. What is the z-score of 79?

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Question 5

A variable is normally distributed with mean 58 and standard deviation 11. About what percentage of values lie between 47 and 69?

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Question 6

Scores have mean 49 and standard deviation 3. What is the z-score of 55?

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Question 7

A variable is normally distributed with mean 148 and standard deviation 13. About what percentage of values lie between 109 and 187?

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Question 8

Scores have mean 77 and standard deviation 2. What is the z-score of 82?

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Question 9

A variable is normally distributed with mean 139 and standard deviation 14. About what percentage of values lie between 125 and 153?

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Question 10

Scores have mean 117 and standard deviation 10. What is the z-score of 107?

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Question 11

A variable is normally distributed with mean 138 and standard deviation 14. About what percentage of values lie between 110 and 166?

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Question 12

Scores have mean 111 and standard deviation 12. What is the z-score of 135?

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Question 13

A variable is normally distributed with mean 81 and standard deviation 5. About what percentage of values lie between 66 and 96?

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Question 14

Scores have mean 44 and standard deviation 11. What is the z-score of 71.5?

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Question 15

A variable is normally distributed with mean 102 and standard deviation 5. About what percentage of values lie between 97 and 107?

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Question 16

Scores have mean 42 and standard deviation 10. What is the z-score of 47?

Answer