# The area of circle problems

#### Number of problems found: 158

• Area of a circle The circumference of the circle is 150.72 centimeters. Calculate the area of the circle.
• Circle simple Circumference of a circle is 6.28. What is the area of the circle?
• Circle area Calculate the circle area with a radius of 1.2 m.
• Circle and rectangle 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 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 Calculate the area of a circle in dm2 if its circumference is 31.4 cm.
• Circles 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 Calculating side of the square with the same area as the circle of radius 18.
• Circular flowerbed 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 How big is an area of a circle if its circumference is 80.6 cm?
• Concentric circles 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 Find the area of a circle whose diameter is 26cm.
• Three shapes 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 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 Calculate circle circumference if its area is 254.34cm2
• Perimeter to area Calculate the area of a circle with a perimeter of 15 meters.
• 22/7 circle Calculate approximately the area of a circle with radius 20 cm. When calculating π, use 22/7.
• Equilateral triangle vs circle 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 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 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.