The area of circle problems

Number of problems found: 158

  • Area of a circle
    circle5 The circumference of the circle is 150.72 centimeters. Calculate the area of the circle.
  • Circle simple
    circles_3 Circumference of a circle is 6.28. What is the area of the circle?
  • Circle area
    circle3 Calculate the circle area with a radius of 1.2 m.
  • Circle and rectangle
    described_circle A rectangle with sides of 11.7 cm and 175 mm is described by circle. What is its length? Calculate the content area of the circle described by this circle.
  • Two annuluses
    medzikruzie_2 The area of the annular circle formed by two circles with a common center is 100 cm2. The radius of the outer circle is equal to twice the radius of the inner circle. Determine the outside circle radius in centimeters.
  • Circle - simple
    colorful-circle Calculate the area of a circle in dm2 if its circumference is 31.4 cm.
  • Circles
    SquareCircleSquare The area of a circle inscribed in a square is 14. What is the area of a circle circumscribed around a square?
  • Squaring the Circle
    SquareCircle Calculating side of the square with the same area as the circle of radius 18.
  • Circular flowerbed
    sustredene_kruznice Circular flowerbed with diameter 8 m we split by concentric circle to circle and annulus with the same area. Find the radius of the circle.
  • Circle
    circle How big is an area of a circle if its circumference is 80.6 cm?
  • Concentric circles
    medzikruzie2 There is given a Circle K with a radius r = 8 cm. How large must a radius have a smaller concentric circle that divides the circle K into two parts with the same area?
  • Diameter to area
    circle_eq_1 Find the area of a circle whose diameter is 26cm.
  • Three shapes
    three_bodies 1/5 of a circle is shaded. The ratio of area if square to the sum of area of rectangle and that of the circle is 1:2. 60% of the square is shaded and 1/3 of the rectangle is shaded. What is the ratio of the area of circle to that of the rectangle?
  • Circular ring
    mezikruzi Square with area 16 centimeters square are inscribed circle k1 and described circle k2. Calculate the area of circular ring, which circles k1, k2 form.
  • Area to perimeter
    circle11_3 Calculate circle circumference if its area is 254.34cm2
  • Perimeter to area
    circles_1 Calculate the area of a circle with a perimeter of 15 meters.
  • 22/7 circle
    red_circle Calculate approximately the area of a circle with radius 20 cm. When calculating π, use 22/7.
  • Equilateral triangle vs circle
    rs_triangle Find the area of an equilateral triangle inscribed in a circle of radius r = 9 cm. What percentage of the circle area does it occupy?
  • Circle in rhombus
    circle_rhombus In the rhombus is an inscribed circle. Contact points of touch divide the sides to parts of length 19 cm and 6 cm. Calculate the circle area.
  • Diameters of circles
    circle5_1 How many percent of the area of a larger circle is a smaller circle if the smaller circle has a diameter 120 mm and a larger one has a diameter 300 mm?

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Examples of area of plane shapes. Circle Problems.