Question
Quantitative Aptitude Question on Circles
In a circle, two parallel chords on the same side of a diameter have lengths 4 cm and 6 cm. If the distance between these chords is 1 cm, then the radius of the circle, in cm, is
A
√12
B
√14
C
√13
D
√11
Answer
√13
Explanation
Solution
The correct answer is (C):
Let the 6 cm long chord be x cm away from the centre of the circle. Let the radius of the circle be r cm.
The perpendiculars from the centre of the circle to the chords bisect the chords.
r2=x2+32=(x+1)2+22
Solving, x=2 and r=√13