SSC CHSL 2020 PYQ — Question 53

SSC CHSL - 13th October 2020 - Shift 2 • Quantitative Aptitude • Q53

In  the following figure (not to scale), at the centre O, if the chord AB subtends double the angle that is subtended by chord CD and the angle ∠AEB = 2∠AOB, then ∠COD is equal to:

Show answer & explanation

Correct answer: A

Explanation

The correct answer is option 1 i.e 30o

Understanding Application
Angle made on a tangent is perpendicular to the radius.

Given that,

⇒ ∠AEB = 2 ∠AOB

&

⇒ ∠AOB = 2 ∠COD

We can infer that

⇒ ∠OBE = ∠OAE = 90°(By the given property)

In quadrilateral AOBE

⇒ ∠AOB + ∠AEB + ∠OBE + ∠OAE = 360°

⇒ ∠AOB + ∠AEB + 90° + 90° = 360°

⇒  ∠AOB + 2 × ∠AOB = 180°

⇒ ∠AOB = 60°

⇒ 2 ∠COD = 60°

⇒  ∠COD = 30°