Area of the sector of a circle with radius \(7 \text{ cm}\) and the angle at the centre is \(270^\circ\) is _____ \(\text{cm}^2\).
Show Hint
A full circle has:
\[
360^\circ
\]
So:
\[
270^\circ = \frac{3}{4}
\]
of the entire circle.
Therefore, this sector is simply:
\[
\frac{3}{4}\times \pi r^2
\]