Final answer:
The area of a circle with a diameter of 5 cm is approximately 20 cm² when rounded to the nearest whole number, calculated using the formula A = πr².
Step-by-step explanation:
To find the area of a circle with a diameter of 5 cm, you first need to calculate the radius (half of the diameter) which in this case is 2.5 cm. The formula for the area of a circle is A = πr², where A is the area, r is the radius, and π (pi) is approximately 3.14159. After plugging in the radius, we get:
A = π(2.5 cm)²
= 3.14159 • (2.5 cm • 2.5 cm)
= 3.14159 • 6.25 cm²
= 19.635 cm²
Rounded to the nearest whole number, the area of the circle is approximately 20 cm².