10 Views

Question : In the given figure, O is the centre of the circle, $\angle DAB=110^{\circ}$ and $\angle BEC=100^{\circ}$. What is the value (in degrees) of $\angle OCB$?

Option 1: 5

Option 2: 10

Option 3: 15

Option 4: 20


Team Careers360 21st Jan, 2024
Answer (1)
Team Careers360 24th Jan, 2024

Correct Answer: 10


Solution : Given, $\angle DAB=110^{\circ}$ and $\angle BEC=100^{\circ}$
Since the angle subtended by the chord at the centre is double the angle subtended by the chord at the circumference,
reflex$\angle BOC = 2\angle BEC = 200^\circ$
So, $\angle BOC = 360^\circ-200^\circ = 160^\circ$
By angle sum property in $\triangle BOC$,
$\angle BOC + \angle OCB+ \angle OBC =180^\circ$
⇒ $160^\circ+ 2\angle OCB =180^\circ$ ($\angle OCB = \angle OBC$ since OB and OC are radii of same circle)
⇒ $\angle OCB = 10^\circ$
Hence, the correct answer is 10.

Know More About

Related Questions

Amity Online MBA
Apply
Apply for an Online MBA from Amity Online.
Manipal Online M.Com Admissions
Apply
Apply for Online M.Com from Manipal University
View All Application Forms

Download the Careers360 App on your Android phone

Regular exam updates, QnA, Predictors, College Applications & E-books now on your Mobile

150M+ Students
30,000+ Colleges
500+ Exams
1500+ E-books