Question

circle o has a circumference of approximately 28.3 cm. what is the approximate length of the radius, $r$?4.5 cm9.0 cm14.2 cm28.3 cm

Explanation:

Step1: Recall circumference formula

The formula for the circumference $C$ of a circle is $C = 2\pi r$.

Step2: Rearrange to solve for $r$

Isolate $r$ by dividing both sides by $2\pi$:
$r = \frac{C}{2\pi}$

Step3: Substitute given value

Substitute $C = 28.3$ cm and use $\pi \approx 3.14$:
$r = \frac{28.3}{2\times3.14} = \frac{28.3}{6.28} \approx 4.5$

Answer:

A. 4.5 cm