Apps. and Interpretation for IBDP Maths Ebook 1 | Page 165

44
Example
Paper 1 – Areas and Perimeters of Sectors
13
The following diagram shows a circle with centre O and radius 100 cm.
The points A , B and C are on the circumference of the circle and
AOC ˆ � 86 .
(a) Find the length of arc ABC .
(b) Find the perimeter of sector OABC .
(c) Find the area of sector OABC .
[2]
[2]
[2]
Solution
(a)
(b)
The length of arc ABC
86
�2 � (100) �
360
(A1) for substitution
� 150.0983157
� 150 cm
A1 N2
The perimeter of sector OABC
�150.0983157 �100 � 100
(M1) for valid approach
� 350.0983157
� 350 cm
A1 N2
[2]
[2]
www.seprodstore.com
155