PrepRung

CAT 2018 Slot 1 · Quant · Circles · easy

What is the length of a chord at a distance of 8 cm from the centre?

Single correct option

In a circle, a chord of length 16 cm is at a distance of 6 cm from the centre. What is the length of a chord at a distance of 8 cm from the centre?
  1. A. 15 cm
  2. B. 10 cm
  3. C. 12 cm
  4. D. 14 cm
Show answer and solution

Answer: (C) 12 cm

The perpendicular from the centre bisects the chord. For the first chord: r² = 8² + 6² = 100, so r = 10 cm.

For a chord at distance 8 cm: half-length = √(100 − 64) = 6 cm, so the chord is 12 cm.

Tip: Chord = 2√(r² − d²). Recognise the 6-8-10 triple.
Report a mistake

Original question written in the CAT 2018 Slot 1 pattern and checked twice for the correct answer. Not an official question paper. How we write and check questions · Corrections policy · Report a mistake