Apps. and Interpretation for IBDP Maths Ebook 1 | Page 247

(d) The number of workers earned not more than $k
�80 � 10
(M1) for valid approach
� 70
(A1) for correct value
k � (20)(30) � (30)(40 � 30)
(A1) for correct formula
k � 900
A1 N4
(e) Systematic sampling A1 N1
[4]
[1]
Exercise 70
1. The following cumulative frequency curve shows the amounts in dollars raised by all the
students in the school.
17
(a) (i) Write down the inter-quartile range of the amount in dollars raised.
(ii) Write down the number of students who raised between 15 dollars and 20
dollars.
[3]
www.seprodstore.com
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