Question

A circular piece of metal has a radius of 3.5 meters.
The metal sells for $3.25 per square meter.

What is the total cost of the circular piece of metal?

A.
$11.38

B.
$38.47

C.
$71.44

D.
$125.01

Answer 1

Use the formula for finding the area of a circle, then multiply it by each square meter.

A = π r²
A = π (3.5)²
A = 12.25π
A = 38.485

C = 3.25(38.485)
C = 125.01

Answer = $125.01

Answer 2

Area of circle = πr²

Radius, r = 3.5m,  

Area = πr² = π*3.5*3.5 = 12.25π m²

Area ≈ 12.25 *3.141 ≈ 38.477 m²

Since the metal sells for $3.25 per square meter.

Total cost  for 38.477 m² = 38.477 * 3.25 = 125.05

Answer is = $125.05

The answer is not really there, but let's say we can manage option D which is $125.01.