CAT Exam Model Paper 6 with solutions for free online practice

Arc length =

θ

360

×2πr
As the radius is fixed, the arc length is directly proportional to the angle subtended by the arc at the centre. So if the arc length is getting tripled the angle is also getting tripled.
Therefore (0 + 30 + 90 + 270 + 810) =

1

8

.2π
⇒1210=

π

4

⇒θ=

π

484

Angle subtended byA‌2A‌3 at the centre is30
3×

π

484

=

3π

484