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

Number of examples found: 273

  • Two circles
    two_circles Two circles with a radius 4 cm and 3 cm have a center distance 0.5cm. How many common points have these circles?
  • Diameter
     circular_plot The diameter of a circular plot is 14 dm. Find the circumference and area.
  • Star
    cross_star Calculate the content of the shaded part of square with side 28 cm.
  • Find radius
    numbers_49 Find radius of circle using pythagorean theorem where a=9, b=r, c= 6+r
  • Thales
    circles_1 Calculate the length of the Thales' circle described to right triangle with hypotenuse 18.4 cm.
  • Wheel
    wheel_1 What is the wheel diameter if on the 0.38 km track turns 128 times?
  • Wheel
    bicycle_1 Diameter of motocycle wheel is 52 cm. How many times rotates wheel on roand long 2 km?
  • Radius
    green_circle Determine the radius of the circle, if its perimeter and area is the same number.
  • Ruler and compass
    triangle_bac Use a ruler and compass to construct a triangle ABC with AB 5cm BAC 60° and ACB 45°.
  • Rhombus construction
    rhombus_7 Construct ABCD rhombus if its diagonal AC=9 cm and side AB = 6 cm. Inscribe a circle in it touching all sides...
  • Arc
    vysek What area of a circle occupied the flowers planted in the arc of a circle with radius 4 m with central angle 45°?
  • Cylinder - basics
    cylinder Cylinder with base radius r = 45 dm and height h=22 dm. Calculate:
  • Annulus
    medzikruzie.JPG Two concentric circles form an annulus of width 10 cm. The radius of the smaller circle is 20 cm. Calculate the content area of annulus.
  • 10 pieces
    circle_div How to divide the circle into 10 parts (geometrically)?
  • Bridge
    bridge_circle The bridge arc has a span 34 m and height 3 m. Calculate the radius of the circle arc of this bridge.
  • Quadrant II
    quartes_circle Calculate the radius of the quadrant, which area is equal to area of circle with radius r = 15 cm.
  • Described
    desc_circle Calculate perimeter of the circle described by a triangle with sides 478, 255, 352.
  • Circle and angle
    arc What is the length of the arc of a circle with radius r = 207 mm with cental angle 5.33 rad?
  • The chord
    circles_4 Calculate a chord length which the distance from the center of the circle (S, 6 cm) equals 3 cm.
  • Roller
    cestnyvalec Roller has a diameter of 0.96 m and a width 169 cm. How many m2 of road level when he turns 42-times?

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