Page 254 - ABCTE Study Guide_Neat

Area

Recall that the area of a two-dimensional figure is the number of square units it contains. So, the area of a
2
2
circle is given in units like in or ft .

The area of a circle is given by the formula , where r is the radius of the circle.

Question

What is the area of this circle? Round your answer to the nearest square foot.

2
A 188 ft

2
B 707 ft

2
C 903 ft

2
D 2826 ft

Answer

Choice B is correct. The area of the circle is given by the formula . Since the diameter of the circle is
30 ft, the radius is 15 ft. So the area is

If you answered C, you may have added p to the square of the radius rather than multiplying it. If you
answered D, you may have used the diameter in the formula rather than the radius.

Review

• The circumference of a circle is the distance around the circle. It is given by the
formulas , where r is the radius, or , where d is the diameter.

• The area of a circle is given by the formula, , where r is the radius of the circle.