From a point Q, the length of the tangent to a circle is 24 cm and the distance of Q from the Centre is 25 cm. The radius of the circle is.

Let O be the centre of the circle.
Given: OQ = 25 cm and PQ = 24 CM
We Know that the radius is perpendicular to tangent. Therefore, OP ⊥PQ
In ΔOPQ, by pythagoras theorem,
OP² + 24² = 25² ⇒ OP² = 625 – 576 ⇒ OP² = 49 ⇒OP = 7
Therefore, the radius of circle is 7 cm. Hence, the option (A) is correct.