Page 394 - Math Smart - 7

17.1.3 Finding the range

Another way to interpret a set of data is by looking at how the data in the set is
spread out. Let us look at a scenario.

This weather forecast shows the expected temperature at different times of a
day. Linda wants to know the difference between the highest and the lowest
expected temperatures.
Weather Forecast^^^

06 00 07 00 08 00 09 00 10 00 11 00 12 00 13 00 14 00

O O

28°C 27°C 27°C 28°C 29°C 29°C 30°C 30°C 31°C

Which is the highest or lowest temperature? How can you find the difference?
What is the range?

The difference between the highest and the lowest value in a data set is called
the range.

What is the range of these numbers?

14,12, 7,1,5, 9,15,11,19
Solution
Ordering the data from the highest to the lowest, we get:

19, 15, 14, 12, 11, 9, 7, 5, 1

highest value lowest value
The difference between the highest and the lowest value is 19 - 1 = 18.
Spotlight The range of the data set is 18.

An evolutionary I
biologist found that
sprinters with the most
Five people participated in a marathon race. What is the range of their times?
symmetrical knees have
2.9 h, 7.4 h, 3.6 h, 5.8 h, 4.9 h
the best times and this
was especially true of Find the range of these quiz scores.
the 100-m sprinters in 92,81,85, 87, 90, 79, 84
Jamaica.
Find the range of the following hourly wages.
$7.50, $8.75, $9.50, $8.25, $8.50

390 UNIT 17