Glencoe Math: Course 3, Volume 2
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Glencoe Math: Course 3, Volume 2 View details
4. Descriptive Statistics
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Exercise 1 Page 705

The mean is the mathematical average. The median is the middle value. The mode is the most repeated value. The range is the difference between the greatest and least value.

Mean: about 103.1
Median: 100
Mode: 100
Range: 46

Practice makes perfect

We want to find the mean, median, mode and range of the given data set. Let's start by looking at the given table.

Fastest Roller Coaster
Coaster Speed (mph)
Dodonpa 107
Kingda Ka 128
Millennium Force 93
Phantom's Revenge 82
Steel Dragon 2000 95
Superman: The Escape 100
Top Thrill Dragster 120
Tower of Terror 100

Now, we can sort the values in this data set. 82 , 93 , 95 , 100 , 100 , 107 , 120 , 128

Mean

The mean of a data set is calculated by finding the sum of all of the values in the set and then dividing by the number of values in the set. In this case, there are 8 values.

Mean=Sum of values/Number of values
Mean=82 + 93 + 95 + 100 + 100 + 107 + 120 + 128/8
Mean=825/8
Mean=103.125
Mean≈103.1

The mean of the set is 103.1, correct to the nearest tenth.

Median

When the data are arranged in numerical order, the median is the middle value — or the mean of the two middle values — in a set of data. Let's arrange the given values and find the median. 82 , 93 , 95 , 100 | 100 , 107 , 120 , 128 Since there are 8 values, there is no one middle value. Thus, for this exercise, the median is the mean of the two middle values. Median: 100+ 100/2=100

Mode

The mode is the value or values that appear most often in a set of data. Let's find the mode of the given values. 82 , 93 , 95 , 100 , 100 , 107 , 120 , 128 The value that appears most often is 100. Mode: 100

Range

The range is the difference between the greatest and least values in a set of data. For our exercise, the greatest value is 128 and the least value is 82. Range: 128- 82=46