Question

Find the area and circumference of the circle if It is 13 in

Answer 1

Area: 531 in²

Circumference: 82 in

Explanation:

Given:

• radius = 13 inches
• π = 3.14
• round to nearest whole number

To find:

• Area
• Circumference

Area of Circle:

`\displaystyle \large{A=\pi r^2}`

• A = area

Therefore:

`\displaystyle \large{A=3.14 \cdot 13^2}\\\displaystyle \large{A=530.66 }`

Round to nearest whole number:

• If the digit is at least or greater than 5, round to 1.
• If the digit is less than 5, don’t do anything.

Therefore, the area is 531 inches squared

Circumference of Circle:

`\displaystyle \large{C=2\pi r}`

• C = circumference

Therefore:

`\displaystyle \large{C=2\cdot 3.14 \cdot 13}\\\displaystyle \large{C=81.64}`

Round to nearest whole number:

Hence, the circumference is 82 inches