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Pi times r times r or Pi r squared is the formula for finding the area of a circle where r is the radius
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What is the diameter of a circle with a circumference of 27.5 inches?
The circumference of a circle is 2*Pi*R (Pi~3.14) so: 2*Pi*R = 27.5 Pi*R = 13.75 R = 4.37 cm
If the circumference of the circle is 1200 what is the radius?
C = 2 pi r so pi r = 600 so r = 600/pi
What is the formula of a semicircle in perimeter?
The perimeter of a semicircle with radius R is pi*R + 2*R = R*(pi + 2)
Is 2Pi r the same as Pi r squared?
No. 2Pi r is equal to Pi d, though.
What happens to the area of a circle when the radius is tripled?
The area of the circle becomes 9 times the area of the original circle. Original circle = Pi * (r ^ 2) = Pi * r * r New Circle = Pi * ((3 * r) ^ 2) = Pi * 9 * r * r
What is the radius of a circle with circumference of 8 inches?
C = 2*pi*r 8 = 2*pi*r 4 = pi*r r = 4/pi
The girth plus length of parcels sent by fourth-class mail may not exceed 108 inches What is the largest volume of a cylindrical parcel that can be sent by fourth-class mail?
girth = 2PI r height=h h+2 PI r =108 h=108-2 PI r Volume = PI r^2 h V = PI r^2 (108-2PI r) Differentiate with respect to r dV/dr = PI (2r) (108-2PI r) +PI r^2 (-2PI) =0 216 PI r -4 PI^2 r^2 -2 PI^2 r^2=0 216 PI r -6 PI ^2 r^2=0 PI r [ 216-6 PI r] =0 6 PI r = 216 r = 36/PI --- dimensions h = (108-2 PI (36/PI)) = 108 -72=36 -- dimensions Largest volume = PI r^2 h = PI (36/PI)^2 (36) =1,296 / PI d^2V/dr^2 =216 PI -6 PI^2 (2r) when r=36/PI, d^2V/dr2 = 216 PI - 6PI^2 (2)(36)/PI =216 PI -432 PI < 0, indicates V has been maximized.
What is the area of a circle with a circumference of 25.12 cm?
The circumference of a circle: C = 2(pi)r The area of a circle: A = (pi) r^2 C = 25.12 cm 2(pi)r = 25.12 cm r = 25.12/[2(pi)] r = 12.56/pi r^2 = 157.7536/pi^2 So, A = (pi)r^2 A = (pi)(157.7536/pi^2) A = 157.7536/pi A = 50.22 cm^2 (approximately)
What is the radius if area equals 289 pi?
Recall the equation A = pi * r^2. You've given the information that A = 289 pi. Now, simply solve the equation for r: A = pi * r^2 289 pi = pi * r^2 289 = r^2 sqrt(289) = r 17 = r
What is the area of a circle with a circumference of 410 meters?
Circumference = 2pi*r 410 = 2pi*r r = 205/pi A = pi*r^2 A = pi*(205/pi)^2 A = 205^2/pi metres A = 42 025/pi metres
Formula to find circumference of quadrant?
Circumference of a circle = 2 * pi * r pi = 3.1415926535897932384626433832795 r= radius of circle Hence Circumference of a Quadrant = 2 * pi * r / 4 = pi * r / 2 = 0.5 * pi * r For more accurate value of pi, please refer: http://en.wikipedia.org/wiki/Pi
A circle has a circumference of 16 pi inches what is its radius?
The formula where C=circumference, R=radius is C = 2 pi R Since C = 16 pi inches and 16 pi = 2 pi R we can solve for R and get R= 16 pi /2 pi = 8 Therefore the Radius is 8 inches.
If the circumference of a circle is twenty pi then what is its area?
C=2*Pi*r = 20*Pi r=10 A=Pi*r2=Pi*102=100*Pi
What is the diameter of a circle with a circumference of 27.5 inches?
The circumference of a circle is 2*Pi*R (Pi~3.14) so: 2*Pi*R = 27.5 Pi*R = 13.75 R = 4.37 cm
How do you find the are of the base of a cylinder?
SA=2(pi times r squared) + h(pi 2 r) or (easier way) 2 pi r squared + 2 pi r h
What is the formula for circumference in terms of pi?
d * pi or 2 * r * pi Where d is diameter and r is radius and pi = 3.14159
How do you solve v equal pi r square h solve for h?
V = pi*(r^2)*h is the formula for the volume of a cylinder. In order to solve for 'h' (or the height), do the following:V = pi*(r^2)*h --> divide both sides of the equation by pi*(r^2) to get rid of pi*(r^2) on the right side of the equation.V/(pi*(r^2)) = (pi*(r^2)*h)/(pi*(r^2)) --> cancel out the common term (pi*(r^2)) in the right side of the equation.You are left with the original equation in terms of 'h':h = V/(pi*(r^2))
