year 8 maths

9H
Interquartile range
571
5 Calculate the median of the following sets.
a 1, 3, 5, 6 b 2, 7, 8, 12, 14, 15 c 1, 4, 5, 6, 8, 10
6 Consider the set 8, 6, 10, 4, 3, 7, 5, 5 .
a Write this list in ascending order.
b Calculate the lower quartile.
c Calculate the upper quartile.
d Calculate the IQR .
Example 12a
Example 12b
7 Find the IQR of the following sets.
a 1, 9, 11, 13, 28, 29 b 7, 9, 13, 16, 20, 28
c −17, −14, −12, −9, −8, 1, 9, 9, 12, 12 d −20, −20, −10, −3, −1, 0, 3, 5, 14, 18
e 0, 0, 4, 5, 7, 8, 8, 8, 11, 12, 17, 18 f 1, 9, 9, 9, 12, 18, 19, 20
g 0.28, 2.13, 3.64, 3.81, 5.29, 7.08 h 1.16, 2.97, 3.84, 3.94, 4.73, 6.14
8 Find the IQR of the following sets.
a 4, 4, 11, 16, 21, 27, 30 b 10, 11, 13, 22, 27, 30, 30
c −13, −13, −12, −3, 14, 15, 22, 23, 27 d −19, −17, −6, 0, 3, 3, 18, 23, 26
e 1, 1, 2, 9, 9, 12, 18, 18, 18 f 2, 2, 8, 9, 12, 14, 15, 16, 19
g 0.4, 0.9, 0.9, 1.9, 2.0, 3.9, 4.3, 4.4, 4.7 h 0.5, 1.1, 1.2, 1.4, 1.5, 2.1, 2.2, 2.4, 4.8
9 Find the IQR of the following sets. Remember to sort first.
a 0, 12, 14, 3, 4, 14 b 14, 0, 15, 18, 0, 3, 14, 7, 18, 12, 9, 5
c 6, 11, 3, 15, 18, 14, 13, 2, 16, 7, 7 d 6, 4, 6, 5, 14, 8, 10, 18, 16, 6
e 18, −15, 17, −15, −1, 2 f −12, −17, −12, 11, 15, −1
g −19, 8, 20, −10, 6, −16, 0, 14, 2, −2, 1 h −4, −9, 17, 7, −8, −4, −16, 4, 2, 5
PROBLEM-SOLVING AND REASONING
10, 11, 15 11–16
12–17
10 Gary and Nathan compare the number of runs they score in cricket over a number of weeks.
Gary: 17, 19, 17, 8, 11, 20, 5, 13, 15, 15
Nathan: 39, 4, 26, 28, 23, 18, 37, 18, 16, 20
a Calculate Gary’s range.
b Calculate Nathan’s range.
c Who has the greater range?
d Which cricketer is more consistent, on the basis of their ranges only?
11 Winnie and Max note the amount of water they drink (in litres) every day for a week.
Mon Tue Wed Thu Fri Sat Sun
Winnie 2.4 1.3 3 2.2 2 4 1.2
Max 1.5 2.3 0.8 1.2 3 2.5 4.1
a Calculate Winnie’s IQR .
b Calculate Max’s IQR .
c Who has the larger IQR ?
Cambridge Maths NSW
Stage 4 Year 8 Second edition
ISBN 978-1-108-46627-1 © Palmer et al. 2018
Cambridge University Press
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