What is the radius of a circle with the area of 49 pi?

Cancelling π, we get r²=49 cm so r=7 cm.

How do you find the diameter of a circle with the area?

Divide the area (in square units) by Pi (approximately 3.14159). Take the square root of the result (Example: 310.56). This is the radius. Now double the radius to get the diameter (Example: 621.12 meters).

How do you find the diameter of a circle using pi?

Divide the circumference (perimeter) by pi. That gives you the diameter. Half of that is the radius. To get the area, square the radius, and then multiply by pi.

What is the diameter of a circle with an area of 16 pi?

We see that our radius is √16 , or 4 . Recall that the diameter is twice the length of the radius, so we can multiply this by 2 to get a diameter of 8 .

How do we find the radius of a circle?

How to Find the Radius of a Circle?
1. When the diameter is known, the formula is Radius = Diameter/ 2.
2. When the circumference is known, the formula is Radius = Circumference/2π.
3. When the area is known, the formula for the radius is Radius = ⎷(Area of the circle/π).

What is a diameter of a circle?

Circle/Diameter

Just remember to divide the diameter by two to get the radius. If you were asked to find the radius instead of the diameter, you would simply divide 7 feet by 2 because the radius is one-half the measure of the diameter.

What is the pi value?

Succinctly, pi—which is written as the Greek letter for p, or π—is the ratio of the circumference of any circle to the diameter of that circle. … In decimal form, the value of pi is approximately 3.14.

How do you find the circumference of a DIA?

How do I find the diameter from the circumference?
1. Divide the circumference by π, or 3.14 for an estimation.
2. And that’s it; you have the circle’s diameter.

What is the area of a diameter?

Answers. 1. The formula for the area A as a function of the diameter d of a circle is given by A = π (d/2)^2.

Is girth a circumference?

Girths are circumference measures at standard anatomical sites around the body. It is measured with a tape and can be used in determining body size, composition and to monitor changes in these parameters.

How do you find the circumference and area of a circle?

To find the circumference, you double the radius and multiply by pi. To find the area, you square the radius and multiply by pi.

Is pi the area of a circle of diameter 1?

The area of a circle is pi times the radius squared (A = π r²). Learn how to use this formula to find the area of a circle when given the diameter.

Why is pi used to calculate the area of a circle?

In basic mathematics, pi is used to find the area and circumference of a circle. Pi is used to find area by multiplying the radius squared times pi. … Because circles are naturally occurring in nature, and are often used in other mathematical equations, pi is all around us and is constantly being used.

Is Pi the circumference of a circle diameter 1?

Here the Greek letter π represents a constant, approximately equal to 3.14159, which is equal to the ratio of the circumference of any circle to its diameter.

Is Pi the circumference of a circle of diameter one?

Circles are all similar, and “the circumference divided by the diameter” produces the same value regardless of their radius. This value is the ratio of the circumference of a circle to its diameter and is called π (Pi).

Why is the area of a circle πr2?

We can clearly see that one of the sides of the rectangle will be the radius and the other will be half the length of the circumference, i.e, π. As we know that the area of a rectangle is its length multiplied by the breadth which is π multiplied to ‘r’. Therefore, the area of the circle is πr2.

How do you find pi?

The formula for the value of pi is the ratio of the circumference of a circle to its diameter. In the ratio form, it is represented as π = Circumference/Diameter.

Which of these is equivalent to π?

The value of Pi (π) is the ratio of the circumference of a circle to its diameter and is approximately equal to 3.14159. In a circle, if you divide the circumference (is the total distance around the circle) by the diameter, you will get exactly the same number.

What formula is 2 pi r?

Circumference (C in black) of a circle with diameter (D in cyan), radius (R in red), and centre (O in magenta). Circumference = π × diameter = 2π × radius.