how do I find the estimated circumference of a circle that is 7 feet in diameter?
350225
C=2*π*r\n\nC-circumference\nr-radius\n\nd=7=2*r\n\nr=7/2\n\nC=2*π*(7/2)\n\nC=7π=7*3.14=22
183956
Half the diameter, or circumference divided by 2.pi
577740
Imagin 2 circles. \n\nTake the first which is the 10'diameter center and add 6ft (3ft walk twice) for a total od 16' diameter. So that radius is half the diameter or 8'.\n\nSo that area is A=3.14(r^2) or 3.14(8^2)=200.96\n\nThen find the area of the inside foundation that is 10' in diameter or 5' radius.\n\nso that area A=3.14(r^2) or 3.14(5^2)=78.5\n\nnow subtract the two areas to get the sidewalk area.  \n\n200.96-78.5=122.46\n\nIt may help if you draw it out. Then you can see how subtracting the foundation area from the entire area will give you the answer.
408251
Measure the diameter and multiply by pi (3.1415)
44824
find the circumference using C=2(pi)r. r is half of the diameter, so thats 2 times pi times 112.5. this is your distance. speed is distance over time. so now you need to convert minutes to seconds so you can get it in m/s. so you do 10 x 60 and that's 600 seconds. so you just divide the circumference divided by 600 and thats your answer.
1106432
Diameter == 10.\nRadius == 5.\nCenter == (1,7)\n\nMethod: use Pythagorean Theorem.
870435
The three questions you could have are:\n1. What is the diameter of the bicycle wheel?\n2. What is the radius of the bicycle wheel?\n3. What is the area of the bicycle wheel?\n\nKnowing that the equation for circumference is c=pi*radius (also c=2*pi*radius), you can solve for the first question by dividing the circumference by pi.\nNote: * = multiply  C= the distance 256.3cm\n\n1. 256.3cm/ pi = 81.5828... = approx. 81.58cm\n\nThe radius is half of the diameter and so:\n2. 81.58cm/2 = 40.79 cm\n\nFinally, the area of the circle can be found with the equation A = pi*(radius)^2\n3. Area= pi*(40.79cm)^2 = pi*(1663.8241) = 5227.05756...= approx. 5227.06cm^2\n\nHope this helps!  You could consider this solving backwards because you are continuously using information that is given or solved for and plugging the values back into different equations.
667615
I'm sorry, miscalculated\nArea of a Circle= pi r^2\n3.14 x (5)^2\n3.14 x 25\nArea of the Circle is 78.5 meters
1008862
circumference = pi * D\n\nwhere D is the diameter.
71470
3.1416 X radius squared\n12" circle= 6" radius\n6" X 6" = ? X 3.1416(pi)= ?\nGot the picture?\nNot going to do your homework for you.\n\n(sorry Lucky Lady but pi X diameter is the circumference)
160871
Divide 34 by PI...that will give you the diameter.\n\nDiameter = Circumference / PI
724249
3.14 inch !! Surprised No? Here is te answer, when we  tie apiece of string around the earth so that it touches all the way around means , we are calculating the circumference of the cross section of the earth.\n\nLet R be the radius of the cross section which is a circle, then coircumference will be\n\n2(Pie)R\n\nNow to get the string 1/2 an inch away from the surface, we need to increase the radius by 1/2 an inch, Thus the new circum ference will be\n\n2(pie) x(R+1/2)\n\n= 2(Pie)R + 2(Pie)/2\n\n=2(Pie) R + Pie\n\nDifference in the new circumference and old will be the difference in the length of the string which will be equal to\n\n2(Pie)R + Pie -2(Pie)R = Pie\n\n\nand value of Pie is 22/7 =3.14, Since we have taken inch as our Unit, Answer will be 3.14 inches more string would be required.
289682
circumference = pie times diameter\nradius is half of the diameter\n\nso if you have either the circumference or the diameter, you can figure it out.
233873
If the square is 7 inches across, then the answer is 38.48 or 3.15159 X (3.5 X 3.5)\n\nIf the circle is 7 inches around the answer is 3.899.
1150077
Any length greater or equal the circumference of a 1-acre circle. \n\nCalculate the acre as square feet, square yards or square meters.\n\nDivide by pi and calculate the square root to get the radius, then multiply by 2 pi for the circle circumference.
392733
Divide the circumference of a circle its diameter.
749836
The 14 foot line is called a secant.  Bisect it, and draw a radius through the point of bisection.  You now have two identical right triangles, with hypotenuses of 12 feet, and known sides of 7 feet.  Use trigonometry to calculate the angle at the center of the circle of either triangle, and then a simple proportion (involving the circle's total circumference) will give you the arc length you want.