JAMB Mathematics 2025 Objective — Question 9

Question 9 of 40 from the Joint Admissions and Matriculation Board (JAMB) Mathematics 2025 Objective paper, with the correct answer and a full explanation.

The length of a chord in a circle is 12cm and the perpendicular distance from the centre to the chord is 5cm. What is the radius of the circle?

• A. 7cm
• B. 8.3cm
• C. 7.8cmCorrect
• D. 5.3cm

Explanation

By Pythagoras: r² = 6²+5² = 61, r = √61 ≈ 7.8cm.

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