Circle - 8th grade (13y) - math problems

Number of problems found: 292

  • Square and circle
    circle_square Into square is inscribed circle with diameter 10 cm.What is difference between circumference square and circle?
  • Circumscription
    circles43 Calculate radius of the Circumscribed circle in the rectangle with sides 20 and 19. It can be rectangle inscribed by circle?
  • Circle chord
    circleChord What is the length x of the chord circle of diameter 115 m, if the distance from the center circle is 11 m?
  • Circle r,D
    bavlnka Calculate the diameter and radius of the circle if it has length 26.59 cm.
  • 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 - simple
    colorful-circle Calculate the area of a circle in dm2, if its circumference is 31.4 cm.
  • Desribed circle to rectangle
    rectangle_in_circle_1 Rectangle with sides 6 cm and 4 cm was circumscribed circle. What part of the content of the circle determined by the circumscribed circle occupies a rectangle? Express in perctentages(%).
  • 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.
  • Chord MN
    lyra_tetiva Chord MN of circle has distance from the center circle S 120 cm. Angle MSN is 64°. Determine the radius of the circle.
  • 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.
  • Hexagon in circle
    hexagon_3 Calculate the radius of a circle whose length is 10 cm greater than the circumference of a regular hexagon inscribed in this circle.
  • Squaring the Circle
    SquareCircle Calculating side of the square with the same area as the circle of radius 18.
  • Circle's chords
    twochords In the circle there are two chord length 30 and 34 cm. The shorter one is from the center twice than longer chord. Determine the radius of the circle.
  • 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?
  • Rectangle and circle
    rectangle_circle_desc The rectangle ABCD has side lengths a = 40 mm and b = 30 mm and is circumscribed by a circle k. Calculate approximately how many cm is circle long.
  • 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.
  • Circle chord
    circles_6 Calculate the length of the chord of the circle with radius r = 10 cm, length of which is equal to the distance from the center of the circle.
  • OK circle
    circles2 Calculate the radius (circumradius) of the circle described right triangle with hypotenuse long 33 and one cathetus long 17.
  • Inscribed circle
    vpisana The circle inscribed in a triangle has a radius 3 cm. Express the area of the triangle using a, b, c.
  • Perimeter of circle
    thalet_1 Calculate the circumference of described circle to the triangle with sides 9,12,15 cm.

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