Standard Deviation Answers

Fiona recorded the number of miles she biked each day last week as shown below.4, 7, 4, 10, 5The mean is given by m = 6. Which equation shows the variance for the number of miles Fiona biked last week?

Yuri computes the mean and standard deviation for the sample data set 12, 14, 9, and 21. He finds the mean is 14. His steps for finding the standard deviation are below.What is the first error he made in computing the standard deviation?

A set of data has a mean of 12 and a standard deviation of 3. A data point of the set has a z-score of 1.3. What does a z-score of 1.3 mean?

The mean of a set of credit scores is and . Which credit score is within a z-score of 3.3?

A missing data value from a set of data has a z-score of –2.1. Fred already calculated the mean and standard deviation to be and . What was the missing data value? Round the answer to the nearest whole number.

A set of data has a mean of 0.5 and a standard deviation of 0.01. A data point of the set has a z-score of 2.5. What does a z-score of 2.5 mean?

A poll worker analyzing the ages of voters found that and . What is a possible voter age that would give her zx = 1.14? Round your answer to the nearest whole number.

Mrs. Rodrigues wants to compare the spread of the test scores of her two biology classes. Which statistic should she use?

The number of cars sold at a dealership over several weeks is given below.14, 23, 31, 29, 33What is the standard deviation for this set of population data?Standard deviation:

The test scores of a geometry class are given below.90, 75, 72, 88, 85The teacher wants to find the variance for the class population. What is the value of the numerator of the calculation of the variance?Variance: