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Area = pi * (radius^2)
Where (radius^2) is radius squared, or radius to the second power.
do some algebraic steps:
Area / pi = radius^2
radius^2 = Area / pi
square root (radius^2) = square root (Area / pi)
radius = (plus or minus) square root (Area / pi)
If you are not working with imaginary numbers then
radius = square root (Area / pi)
What else can I help you with?
What is the area of a hollow cylinder with an outside diameter of 100mm and inside diameter of 30mm?
Not clear which area you want. The surface area of the cylinder can only be determined if you give the length of the cylinder as well as its diameter. As you don't give this I conclude you want the area of the ends only. Each end will be the difference between the area of the 100 mm circle and the 30 mm circle. 100 mm diameter area = 7855 sq mm. 30 mm diameter area = 707 sq mm. Therefore area of end = 7148 sq mm, and you have two ends so total = 14296 sq mm
How do you figure circumference of a circle?
The formula to figure out the circumference (area around the circle) of a circle ispi(3.14) times radius^2 ( to the second power).Now there are ways people can trick you like they give you the diameter but radius is 1/2 of the diameter so you have to divide the diameter by 2.See this example:A circle has a diameter of 12 feet. What is the area of the circle?So now you would have two divide 12 by 2 which equals 6. 6^2=36Now multiply 36 and 3.14 that would equal 113.04.That is the area of the circle 113.04.
What is the area of a circle with a diameter of 5 feet?
The area would be found by taking the square of 2.5 feet, and then multiplying that square by the value of pi, approximately 3.14. So the product = 2.5 ft X 2.5 ft X 3.14 will give you the area of a circle that has a diameter of 5 feet. This comes from the formula for the area of a circle: A = pi X r2
How do you find the diamiter of a circle?
well you can divide the circumference by pi (3.14) and it will always give you the diameter or you could measure it.
How do you find the radius of a circle having the circumfernce?
Divide the circumference by Pi (3.14159), and that will give you the diameter. Divide that number by 2 to find the radius.
How do you find area of a circle when you have the circumference circle?
Divide the circumference by pi, and that will give you the diameter. Then take half of the diameter (the radius), and plug it into the formula for the area of a circle (A=πr²)
How do you work out the area of a circle with only the diameter?
By dividing the diameter by 2 will give the circle's radius. Area of any circle = pi*radius squared.
How do you find the circumference with no radius or diameter?
They would have to give you enough information to eventually get the diameter. If they gave you the area of a circle and asked for the circumference, you can determine the radius, and from the radius the diameter, and then the circumference. If they said "What is the circumference if the area of a circle is 36pi?" Area of a circle is pi*r2, which would give us a value for r = 6 Diameter is 2*r, or = 12. Circumference is d*pi, or 12pi
How do you find the radius of a circle if you are give the diameter?
The radius is half the diameter.
How do you use the diameter to find the circumference of a circle?
Multiplying the diameter by pi (approx 3.1416) will give you the circumference of the circle.
How do you find the circumference of a circle when they give you the diameter?
You multiply the diameter by pi, which is approximately 3.1416.
How do you find out the the diameter of a circle if knowing the circumference?
Divide the circumference by the value of Pi - that will give you the diameter.
How do you find the area of a circle if the circumference is 10?
We know that the area of a circle is pi * r2. We also know that the circumference of a circle is pi * d. Therefore, when you know the circumference of a circle and want to know the area, divide the circumference by pi to give you the diameter of the circle, divide the diameter by 2 to give you the radius, square the radius and then multiply by pi to get the area. So, 10/pi = 3.183. 3.183/2 = 1.5915. 1.59152 = 2.533 2.533 * pi = 7.958 to 3 decimal places. The area of your circle is therefore 7.958cm2.
What is the approximate area of a circle that has a diameter of 12 cm?
Approximately 100, give or take
How do you find diameter if you have the area?
You need to give the shape.
How do you calculate the diameter and the circumference of a circle?
Doubling the radius will give the diameter and times this by pi will give the circumference of the circle.
How do you work out tha area of a circle?
Assuming you know the radius or diameter...(Pi) x (radius) x (radius) or (1/4 Pi) x (diameter) x (diameter) will give you the area.
