Box PlotsExample

The number of passengers in a 72-seater aeroplane was noted on each

of its 20 flights in one day.

48, 54, 72, 21, 37, 45, 72, 41, 59, 63, 54, 59, 68, 72, 70, 64, 41, 32, 24,

31

a) Work out the three quartiles for this data.

b) Draw a box plot for this data.

10 20 30 40 50 60 70 800

Example

The Stem and leaf diagram below represents the scores obtained by 40 boys in a test.

a) Find the median & interquartile range for this information

b) Draw a box plot for the data.

0 5 5 6 8 8

1 1 3 5 6 7 7

2 2 2 5 8 9 9

3 0 1 2 6 8 8 9

4 1 1 1 4 5 6 7 7

5 0 2 2 5 6 7 8

6 0

10 20 30 40 50 600

ExampleThe cumulative frequency

diagram opposite represents the scores obtained by 40 girls in a test.

a) Find the median & interquartile range for this information

b) Draw a box plot for the data.

10

20

30

40

10 20 30 40 50 600

10 20 300

Example

The box plots below represent the scores obtained by Alan and Robert in a game of golf.

Comment on their findings

Alan

Robert