Question

The diameter of a circle is 3 cm. Find its area to the nearest tenth.

Answer 1

Answer:

Its area to the nearest tenth is 7.1 cm^2.

Step-by-step explanation:

Step 1. First, you have to figure out the radius of the circle. Since you know the diameter, simply divide the diameter of 3 by 2 to get the radius of 1.5.

Step 2.

Next, use the formula area = π(radius)²  to figure out the circumference by plugging in the radius. Since we know the radius is 1.5, we can substitute 1.5 for the r in the equation to make it look like this:

a = π(1.5)²

Then, following the order of operations, we solve.

a = π(1.5)²

1.5(1.5) = 2.25

a = π2.25

π ≈ 3.14

(3.14)2.25 = 7.06500

Step 3.

Now, we round 7.06500 up to 7.1.

Therefore, the area of a circle with a diameter of 3 cm rounded to the nearest tenth is 7.1 cm^2.

Answer 2

Answer:

7.1 cm^2

Step-by-step explanation:

Diameter= 2*r

So radius= d/2

Plug in d for 3

Radius: 3/2

Area of a circle: Pi* r*r

So: Pi* 3/2* 3/2

Area= 7.065 which is around 7.1