The problem asks for the approximate area of a regular hexagon inscribed within a circle. The radius of the circle is given as 21 cm.
A regular hexagon inscribed in a circle can be divided into 6 equilateral triangles. The side length of each equilateral triangle is equal to the radius of the circle.
The area of a regular hexagon can be calculated using the formula:
Area = $\frac{3\sqrt{3}}{2} s^2$, where $s$ is the side length.
Substitute the side length ($s = 21$ cm) into the formula:
Now, using the approximate value of $\sqrt{3} \approx 1.732$:
The calculated approximate area is $1145.778 \text{ cm}^2$. Comparing this to the given options, the closest value is 1145 $cm^2$.
Calculate the area of the triangle whose sides are 8 cm, 9 cm and 13 cm. (Rounded up to two decimal places)