The circumference and Area of a circle with a diameter of 4 and 1/3 feet

The formula for circumference is:  $${\mathtt{C}} = {\mathtt{\pi}}{\mathtt{\,\times\,}}{\mathtt{d}}$$ where d is the diameter of the circle.

Therefore, plug in 4 for d, and the circumference would equal  $${\mathtt{4}}{\mathtt{\,\times\,}}{\mathtt{\pi}} = {\mathtt{12.566\: \!370\: \!614\: \!359\: \!173}}$$ . You can write this either as 4 pi or round the decimal.

The formula for area of a circle is: $${\mathtt{A}} = {\mathtt{\pi}}{\mathtt{\,\times\,}}{{\mathtt{r}}}^{{\mathtt{2}}}$$ where r is the radius of the circle. Since radius is half of the diameter, the radius of this circle = 2

And 2² is still 4. So the area would be 4 pi as well, about  12.57.

The difference between the two values for circumference and area of this circle is their units. Area is in units squared.