Exams › SSC CGL (Prelims) › General

Two equal chords, PQ and RS, are at a distance of 12 cm from the center of a circle. If the radius is 20 cm, what is the length of PQ?

1. 16 cm
2. 24 cm
3. 32 cm
4. 40 cm

Correct answer: 32 cm

Solution

For a chord at distance 12 cm from the center in a circle of radius 20 cm, half the chord is \(\sqrt{20^2-12^2}=\sqrt{400-144}=16\) cm. Therefore the full chord length is \(2\times 16=32\) cm. Since equal chords are equidistant from the center, PQ has the same length.

Related SSC CGL (Prelims) General questions

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