Radius of circular sheet(R)$$=4\text{ cm}$$ and radius of removed circle(r)$$=3\text{ cm}$$
Area of remaining sheet$$=$$Area of circular sheet$$-$$Area of removed circle
$$=\pi R^2-\pi r^2=\pi(R^2-r^2)$$
$$=\pi(4^2-3^2)=\pi(16-9)$$
$$=3.14\times 7=21.98 \text{ cm}^2$$
Thus, the area of the remaining sheet is $$21.98\text{ cm}^2$$