find the circumfernce of the given circles 4ft?
114607
Is 4ft the radius or the diameter? (diameter is twice the radius).  Use the formula 2 x 22/7 x r  OR 22/7 x d (both of which are the same since 2r=d)
1174230
I think you have to know how many degrees the segment is.  Then, calculate the area of the entire circle:\n\nPI x radius ^ 2 (squared)\n\nThen, divide the degrees in the segment by 360, so if your segment is 54 degrees, it's:\n\n54/360 = .15\n\nThen, multiply the result of the 2nd calculation (.15 in the example) by the area of the circle you calculated in step 1, and there's your answer.\n\nThere's probably a more elegant way, but it's been 25 years since I took a trigonometry or algebra course.
745252
1) All you need is the circumference, which is pi * diameter, to get the linear distance traveled per revolution.  Then just divide by 100,000 to get it in terms of km, and multiply it by 60 to get it in terms of "per hour".\n\n2) Are you sure you copied this one correctly? The way I figure it, AD = ½ of AB, BE is ½ of BC and CF is ½ of CA.  This means that the left side can be written "4(½AB + ½BC + ½CA).  You then factor out the ½, and you're left with 2(AB + BC + CA), which will always be less than 3(AB + BC + CA)...\n\n3) Start by graphing a right triangle on an X-Y graph with one of the non-right angles at the origin (0,0). Then figure the circle that is formed by the three points of the triangle. When you are finished, the hypotenuse should be the same as a diameter of the circle.\n\nI hope this helps.
203653
http://en.wikipedia.org/wiki/Squaring_the_circle\n\nAll you need is there...
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.
511828
I want to point out first that the formula for perimeter of a circle is (pi)d or 2(pi)r, not (pi)r^2- (pi)r^2 is for the area!\n\nAnyway, P= (pi)d\n         = 8pi\nDivide that by two since it's just a half circle\n         =4pi\nAdd 8 to that, and there you have it, the perimeter!\n\nFinal Answer- 4pi+8 or 20.56cm^2
942591
Chord length = R (see dimensions of rectangle ie flat part of slice)\nSo the size of the angle (θ) subtended at centre of circle is 60° as all sides of the triangle so formed = R.\nSo θ = π/3\n\nSo length of side of rectangle forming curved surface = length of Arc\n= Rθ\n= πR/3\n\nAlso area of segment at either end = ½R²(θ - sinθ)\n= ½R²(π/3 - sinπ/3)\n= ½R²(π/3 - √3/2)\n\nSo total surface area = Area of curved part + area of flat rectangle + 2 * area of end segment\n= πR/3 * 4R + R*4R + 2 * ½R²(π/3 - √3/2)\n= R²(5π/3 + 4 - √3/2)\n\nVolume = Area of segment * height\n= ½R²(π/3 - √3/2) * 4R\n= 2R³(π/3 - √3/2)
711674
the circumference of a circle is the diameter * pi.\n\nor...\n\nC = d * 3.14
634060
The length of one side of the rectangle can be related to the Circumference of the circle.\nTo get the perimeter of a circle, called the circumference of the circle, one simply has to multiply 2 times pi (about 3.14) times the radius of the particular circle. \nThe circumference of a circle can be calculated from its diameter using the formula:\nc = πd\nOr, substituting the radius for the diameter:\nc = 2πr\nWhere r is the radius and d is the diameter of the circle, and π (the Greek letter pi) is the constant 3.141 592 653 589 793...
658093
Given the nature of the values I am assuming they are identifying the circumference.    \nC = 2 * pi * radius = pi * diameter.   \nSo, to find the diameter we would divide out the pi or use 3.14 to get to the diameter for each value.  \nHope this helps.
564499
I assume since you are using pi, then you are relating to a circle.  In circles, perimeter is called circumference, and it found by using the formula pi*2*radius (or pi*diameter).  the answer would therefore be 34.54 units.
310080
Area = pi times radius squared, so divide the diameter by 2 and go from there
926424
The diameter of the circle is the diagonal of the rectangle (as the angle in a seicircle is always 90°)\n\nDiameter = 2 * radius\n= 10 cm\n\nSo by Pythagoras' rule\n\nx² + 8² = 10²\nx² = 100 - 64\n= 36\nx = √36\n= 6\nSo other side is 6 cm
554627
the circumference of a circle can be calculated by using the formula:\n circumference of circle=2*pie*r\n where pie=22/7;it is equal to 3.1415;\n r=radius of the circle.\nThanks.
1048814
If the circles are concentric, just subtract the area of the smaller circle from the larger circle:\n\nArea of small:  6*6*pi\nArea of large:  9*9*pi\n\nDifference of areas = 81*pi   -    36*pi  =  45*pi = 45 * 3.14159  = \n\n141.37 square units
746090
If you want to draw a straight line the same length as the circumference of the circle then first you must measure the radius of the circle. This is the straight-line distance between the centre of the circle and the edge.\n\nThen multiply the length you found for the radius by 2π. This will give you the length of the circumference. i.e:\n\nC = 2πr\n\nTake a ruler and draw a straight line with the same length as the circumference you have just worked out.
385118
the circumference divided by 2 x PI