How do you find the circumference and the area of a circle with diameter 2ft?

Oct 14, 2015

Area = $\pi {\text{ ft}}^{2} \to$ approx 3.14 square feet
circumference = $2 \pi$ ft -> approx. 6.24 feet ($6 \text{ feet " 3 3/8 "inches}$)

Explanation:

Let the radius of a circle be r, then:

Area is $\pi {r}^{2} \to \pi \times {\left(1 \text{ foot}\right)}^{2} = \pi$
Circumference is $2 \pi r \to 2 \times \pi \times 1 \text{foot} = 2 \pi$

The number $\pi$ converted to feet and inches is:
3 feet + approx. $1 \frac{11}{16}$ inches

So using decimals:
area is approx.: $3.14$ square feet
Circumference is approx.: $6.24$ feet