PQRSTV is a regular polygon of side 7 cm inscribed in a circle. Find the circumference of the circle PQRSTV.
A
56 cm
B
22 cm
C
42 cm
D
44 cm
Verified Correct Answer: D.
Step-by-Step Mathematical Solution
Each interior Angle of the polygon = (n-2)180_n
= (6-2)180_6
= 4 x 30
= 120o
i.e ∠PQR = 120o ∴ RQD = 120/2 = 60o also
∴ Δ QOR is equilateral Δ ∴ QO = 7cm
∴ PO = QO = RO ...... = 7cm radius of the circumference of the circle = 2πr
= 2 x 22/7 x 7/1
= 44 cm
Source: Myschool Past Questions Archive (Record #11111)