Question

A chord of a circular clock is 48 inches long, and its midpoint is 7 inches from the center of the circle. What is the radius of the clock to the nearest whole number?

Answer 1

ANSWER

The radius is 25 inches

EXPLANATION

From the diagram, the radius of the circle is AC.

From the Pythagoras Theorem,

${r}^{2} = {7}^{2} + {24}^{2}$

$r^{2} = 49 + 576$

Simplify

$r^{2} = 625$

Take positive square root,

$r = \sqrt{625}$

$r = 25$

Hence the radius is 25 inches