Find the circumference (perimeter) and area of a circle with radius 2.5 feet. Use $\pi$ from a calculator. Choices are rounded to the nearest tenth. A) C = 15.7 ft; A = 19.6 ft² B) C = 7.9 ft; A = 19.6 ft² C) C = 5 ft; A = 6.3 ft² D) C = 10 ft; A = 6.3 ft² E) C = 19.6 ft; A = 15.7 ft²

Question

Quizplus · Accepted Answer

The formula for the circumference of a circle is C = 2$\pi$r, where r is the radius. Plugging in 2.5 for r and using 3.14 (or $\pi$) from a calculator, we get:
C = 2(3.14)(2.5) = 15.7 feet

The formula for the area of a circle is A = $\pi$r$^2$. Plugging in 2.5 for r and using 3.14 (or $\pi$) from a calculator, we get:
A = 3.14(2.5)$^2$ = 19.6 square feet

Therefore, the best choice is A, which gives the correct values for both circumference and area.

Find the Circumference (Perimeter) and Area of a Circle with Radius