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 Arithmetic Mean Unit 8 > Lesson 2 of 8

 Problem: Scott took 7 math tests in one marking period. What is the mean test score? 89,  73,  84,  91,  87,  77,  94 Solution: The sum of these numbers is 595. Dividing the sum by the number of test scores we get: Answer: The mean test score is 85. Definition: The arithmetic mean of a set of data is found by taking the sum of the data, and then dividing the sum by the total number of values in the set. A mean is commonly referred to as an average.

In the problem above, the mean was a whole number. This is not always the case. Let's look at some more examples.

 Example 1: Find the mean driving speed for 6 different cars on the same highway. 66 mph,  57 mph,  71 mph,  54 mph,  69 mph,  58 mph Solution: 66 + 57 + 71 + 54 + 69 + 58 = 375 Answer: The mean driving speed is 62.5 mph.

 Example 2: The Scheuern family drove through 4 midwestern states on their summer vacation. Gasoline prices varied from state to state. What is the mean gasoline price? \$1.79,  \$1.61,  \$1.96,  \$2.08 Solution: \$1.79 + \$1.61 + \$1.96 + \$2.08 = \$7.44 Answer: The mean gasoline price is \$1.86.

 Example 3: A marathon race was completed by 5 participants in the times given below. What is the mean race time for this marathon? 2.7 hr,  8.3 hr,  3.5 hr,  5.1 hr,  4.9 hr Solution: 2.7 + 8.3 + 3.5 + 5.1 + 4.9 = 24.5 Answer: The mean race time is 4.9 hr

 Example 4: Find the mean swimming time rounded to the nearest tenth: 2.6 min, 7.2 min, 3.5 min, 9.8 min, 2.5 min Solution: 2.6 + 7.2 + 3.5 + 9.8 + 2.5 = 25.6 Answer: The mean swimming time to the nearest tenth is 5.1 min.

 Summary: The arithmetic mean of a set of n numbers is the sum of the n numbers divided by n. The mean is commonly referred to as an average.

Exercises

 Directions: Find the mean of each set of data. Click once in an ANSWER BOX and type in your answer; then click ENTER. After you click ENTER, a message will appear in the RESULTS BOX to indicate whether your answer is correct or incorrect. To start over, click CLEAR.

 1 Find the mean of the whole numbers listed below. 1,  8,  7,  6,  8,  3,  2,  5,  4,  5 ANSWER BOX: RESULTS BOX:

 2 Find the mean of the decimals listed below. 5.3,  5.5,  2.2,  4.8,  3.2 ANSWER BOX: RESULTS BOX:

 3 Find the mean rounded to the nearest tenth. 0.34,  0.12,  0.48,  0.56,  0.71,  0.8,  0.65,  0.82 ANSWER BOX: RESULTS BOX:

 4 Employees at a retail store are paid the hourly wages listed below. What is the mean hourly wage? \$7.50,  \$9.25,  \$8.75,  \$9.50,  \$7.25,  \$8.75 ANSWER BOX:  \$ RESULTS BOX:

 5 What is the mean test score? 83,  71,  91,  79,  87,  80,  95,  79,  91,  85,  94,  73 ANSWER BOX: RESULTS BOX:

This in-depth lesson is by Gisele Glosser. You can find me on Google.

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