In the diagram, O is the centre of the circle PQRS, ∠PQR = 72° and OR is parallel to PS. Find ∠ OPS.
Attached Figure / Diagram
A
18°
B
108°
C
54°
D
36°
Verified Correct Answer: D.
Step-by-Step Mathematical Solution
Angle at the centre O is twice the angle at the circumference.
i.e O = 72° * 2 = 144°
∠OPS = 180 - 144 = 36°
Source: WAEC / JAMB / NECO Classroom Archive (Record #61348)