Apps. and Interpretation for IBDP Maths Ebook 1 | Page 235

(b) (i) State whether the data is discrete or continuous.
(ii) Write down the class mark for the class 150 �x
� 200 .
(c)
(iii)
Write down the modal class.
Find an estimate for
[3]
(i)
the mean amount of money, giving the answer in exact value;
(ii)
the standard deviation.
[3]
3. The table below shows the frequency distribution of the scores obtained from their
internal assessment in Mathematics:
17
Scores
Frequency
0�x
� 4
2
4�x
� 8
3
8 �x� f
4
f �x� 16
6
16 �x
� 20
3
It is given that the class widths of all classes are the same, and all scores are positive
integers.
(a) Write down the value of f .
(b) (i) Write down the class mark for the class 16 �x
� 20 .
[1]
(c)
(ii)
Write down the modal class.
Find an estimate for
[2]
(i)
the mean score;
(d)
(ii)
the standard deviation.
Find the greatest possible score that is one standard deviation above the mean
score.
[3]
[2]
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