From an outside point P, two tangents, PA and PB, are drawn to a circle. Given that the length of PA is 12 cm, what is the length…

Quantitative Aptitude ·Previously asked in SSC CGL 2025

View the full solved paper: SSC CGL 2025 Tier I — 17 Sep 2025 (Shift 1)

Question

From an outside point P, two tangents, PA and PB, are drawn to a circle. Given that the length of PA is 12 cm, what is the length of PB?

  1. A. 6 cm
  2. B. 10 cm
  3. C. 12 cm (Correct answer)
  4. D. 24 cm

Correct Answer

Option C — 12 cm

Detailed Solution & Explanation

The correct answer is 12 cm.

Key Points

  • Two tangents drawn to a circle from the same external point are always equal in length.
  • Since PA and PB are both tangents from P, PB = PA = 12 cm.
  • This 'equal tangents from an external point' theorem is a one-line result — no radius, centre or right-angle construction is needed once you recognise both segments are tangents from the same point.

Topics covered: SSC CGL maths Quantitative Aptitude SSC CGL 17 Sep 2025 Q73