Color by Number

Marcus did an experiment to find the average time it takes for a candle to burn. His results are normally distributed. The mean time was 270 minutes with a standard deviation of 32 minutes. What is the z-score for a candle that burned for 300 minutes?

• .94

• .67

• .99

• .85

Monique measured the performance times of middle school orchestra concerts and found a normal distribution. The mean concert time was 48 minutes with a standard deviation of 5.9 minutes. What is the z-score for a time of 40 minutes?

• -1.36

• .94

• 1.36

• -.94

Mrs. Miller’s students took a spelling test last week with a maximum possible score of 30 points. The students’ scores are normally distributed with a mean score of 22. What is the z-score for a student that scored 20? The standard deviation was 2.6.

• -.77

• .77

• 1.85

• -1.85

Maureen is studying the normal distribution of SAT verbal results from her high school. She knows that the mean score was 500 and the standard deviation was 100. What is the z-score for a student that scored 650?

• -1.1

• -1.5

• 1.5

• 1.1

Scores on the verbal section of the SAT are normally distributed with a mean of 500 and a standard deviation of 100. What percentage of test takers scored less than 450?

• 56.5%

• 69.1%

• 30.9%

• 43.5%

Mr. Dawkins assigned an essay to his history classes. Their grades follow a normal distribution. The mean score is 73.5 with a standard deviation of 9.3. What percentage of students who scored more than 90?

• 69.2%

• 30.8%

• 96.2%

• 3.8%

Dominic is tracking his exercise times on the town walking trail. He has normally distributed times with a mean of 48.8 minutes and a standard distribution of 2.1 minutes. What percentage of his exercise times are more than 46 minutes long?

• 9.2%

• 90.8%

• 96.2%

• 3.8%

The average length of a high school soccer game from start to end is 122 minutes. The times are normally distributed with a standard deviation of 2.4 minutes. What percentage of games last less than 120 minutes?

• 20.3%

• 79.7%

• 38.8%

• 61.2%

Given that the weights of Jack Russell Terriers at the Hopkins Animal Shelter are normally distributed with a mean of 15 pounds and a standard deviation of 2.7 pounds. What percentage of Jack Russell Terriers weighs between 13 and 18 pounds?

• 36.3%

• 63.7%

• 78.3%

• 21.7%

College students took a math placement test. Their results are normally distributed with a mean of 68 and a standard deviation of 12. What percentage of students scored between 60 and 75?

• 46.4%

• 53.6%

• 98.7%

• 1.3%