Annulus Problems

Annulus is a ring-shaped object, a region bounded by two concentric circles.

Number of problems found: 28

  • 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.
  • Annulus
    medzikruzie Calculate the area of two circles annulus k1 (S, 3 cm) and k2 (S, 5 cm).
  • Annulus
    medzikruzie_1 The radius of the larger circle is 8cm, the radius of smaller is 5cm. Calculate the contents of the annulus.
  • Circle annulus
    medzikruzie2 There are 2 concentric circles in the figure. Chord of larger circle 10 cm long is tangent to the smaller circle. What are does annulus have?
  • Annulus
    annulus_inscribed_circles Two concentric circles with radii 1 and 9 surround the annular circle. This ring is inscribed with n circles that do not overlap. Determine the highest possible value of n.
  • 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.
  • Annulus from triangle
    annulus2 Calculate the content of the area bounded by a circle circumscribed and a circle inscribed by a triangle with sides a = 25mm, b = 29mm, c = 36mm
  • The collar
    medzikruzie The collar on the dress has the shape of an annulus 6 cm wide. The circumference of the inner circle is 31.4 cm. How much cm2 of fabric is needed to make one collar?
  • Round skirt
    medzikruzie2 The cut on the round skirt has the shape of an annulus. Determine how much m² of fabric will be consumed on an 80 cm long skirt. The circumference of the waist is a circle with a smaller radius and is 69 cm.
  • Annular area
    medzikrucie2 The square with side a = 1 is inscribed and circumscribed by circles. Find the annular area.
  • Around
    zahon_12 Around the circular flowerbed with a radius of 2 m is a sidewalk 80 cm wide. How many square meters does the sidewalk have?
  • Sidewalk
    kruhovy-objazd The city park is a circular bed of flowers with a diameter of 8 meters. Around it, the whole length is 1-meter wide sidewalk. What is the sidewalk area?
  • 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.
  • 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?
  • Concentric circles
    chord_2 In the circle with diameter 19 cm is constructed chord 9 cm long. Calculate the radius of a concentric circle that touches this chord.
  • Shooter
    terc The probability that a good shooter hits the center of the target circle I is 0.1. The probability that the target hit intercircle is II 0.58. What is the probability that it hits the target circle I or II?
  • Brass sphere
    ball1 Find the weight of a brass ball with an outer radius of 12 cm, a wall thickness of 20 mm if the brass's density is 8.5 g/cm3.
  • 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.
  • Round flowerbed
    medzikruzie Around a round flowerbed with a diameter of 6 meters and I will make a sidewalk up to 0.5 meters wide. How much gravel is needed if the layer is to be 5 cm high?
  • Circular lawn
    circular_flowerbed_1 Around a circular lawn area is 2 m wide sidewalk. The outer edge of the sidewalk is curb whose width is 2 m. Curbstone and the inner side of the sidewalk together form a concentric circles. Calculate the area of the circular lawn and the result round to 1

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