What is the area of 19 centimeters?

Let's break this up:

Radius: 19

Diameter: 38

Circumference: 119.4

So...

The area of a circle with radius 19 is 1134

A = πr2 = π(d

2

)2 A = C2

4π

π = 3.1415

A = area

C = circumference or perimeter

r = radius, d = diameter

SOLUTION STEPS:

Area of a circle in terms of radius:

Area = π·r2 = 3.14·192 = 1134 square cm(*)

Area of a circle in terms of diameter:

Area = π·(d

2

)2 = 3.14·(38

2

)2 = 3.14·(19)2 = 1134 square cm(*)

Area of a circle in terms of circumference:

Area = C2

4π

= 119.42

4π

= 14256.36

(4·3.14)

= 14256.36

12.56

= 1134 square cm(*)

(*) 1134.1149479459 cm, exactly or limited to the precision of this calculator (13 decimal places).

Note: for simplicity, the operations above were rounded to 2 decimal places and π was rounded to 3.14.

Result in other units of area:

A circle of radius = 19 or diameter = 38 or circumference = 119.4 cm has an area of:

1.134 × 10-7 square kilometers (km²)

0.1134 square meters (m²)

1134 square centimeters (cm²)

1.134 × 105 square millimeters (mm²)

4.3784 × 10-8 square miles (mi²)

0.135625 square yards (yd²)

1.22063 square feet (ft²)

175.77 square inches (in²)

the least common denominator is 40