Apps. and Interpretation for IBDP Maths Ebook 1 | Page 230

Your Practice Set – Applications and Interpretation for IBDP Mathematics
65
Paper 1 – Measures of Central Tendency and Dispersion
Example
In an examination, the grades of a group of 11 students are as follows:
7 6 4 5 7 4 7 6 2 1 6
(a)
(b)
(c)
(d)
Find the mean of the grades.
Write down the median of the grades.
Write down the mode(s) of the grades.
Write down the standard deviation of the grades.
[2]
[1]
[2]
[1]
Solution
(a) The mean
7 � 6 � 4 � 5� 7 � 4 � 7 � 6 � 2 �1�
6
�
11
(A1) for correct formula
� 5
A1 N2
(b) 6 A1 N1
(c) 6, 7 A2 N2
(d) 1.95 A1 N1
[2]
[1]
[2]
[1]
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