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Delete - Last Modified By: TST at 25/11/2013 4:04:44 PM
The range of a distribution is the difference between the highest and lowest scores.
Range = Highest Score - Lowest Score
The Interquartile range is the difference between the upper quartile (quarter) and the lower quartile (quarter) scores.
Use the following link to learn how to find the Interquartile Range
Edit Delete - Last Modified By: TST at 5/12/2013 10:43:33 AM
Complete the following questions:
1 Calculate the mean, median, mode and range of this set of data:
a 21, 5, 73, 41, 29, 12, 41
b 10.8, 16.7, 0.4, 11.2, 0.1, 18.71, 29.9, 21.4
4 Find the interquartile range of the following sets of data:
a 3, 5, 6, 7, 8, 8, 9, 15
b 2, 3, 3, 6, 7, 10, 12
c 9, 0, 3, 7, 1, 4, 8, 6, 2.
5 For each of the following sets of data, find:
i the median (or Q2) ii QL (or Q1) iii QU (or Q3) iv the interquartile range.
a 12, 18, 13, 10, 12, 16, 15, 15, 19, 17
b 15, 29, 34, 4, 25, 30, 32, 29, 47, 32, 20, 18, 13, 26, 35, 43, 22, 20, 8
c 6.5, 7.9, 8.4, 5.4, 7.5, 8.0, 8.2, 7.9, 9.7, 7.2, 7.0, 9.6, 6.8.
Challenge:
10 In an end of semester test, students in 3 classes obtained the following marks out of 100:
29, 89, 65, 87, 8, 30, 29, 43, 65, 42, 95, 74, 62, 60, 53,
1, 85, 54, 96, 72, 10, 91, 46, 96, 86, 13, 50, 63, 4, 23,
78, 66, 28, 55, 80, 51, 57, 32, 22, 27, 66, 86, 65, 64, 60,
a) Draw up a cumulative frequency polygon to suit the data.
i What should be the pass mark, if 50% of students must pass?
ii The top 5% of students will receive a Distinction award. What is the lowest mark for which such an award can be given?
iii The bottom 25% must repeat this section of the course. How many must repeat? What range of marks falls in this category?
d Determine the interquartile range of the distribution.
Edit Delete - Last Modified By: DSI at 5/12/2013 9:56:49 AM