Area - circles, sectors and segments

  • Two Shapes & Printer Ink
    problem

    Two Shapes and Printer Ink

    Age
    14 to 16
    Challenge level
    1 out of 3

    If I print this page which shape will require the more yellow ink?

  • Efficient packing
    problem

    Efficient Packing

    Age
    14 to 16
    Challenge level
    1 out of 3

    How efficiently can you pack together disks?

  • Round and Round
    problem

    Round and Round

    Age
    14 to 16
    Challenge level
    2 out of 3

    Prove that the shaded area of the semicircle is equal to the area of the inner circle.

  • Small pepper seedlings in turquoise pots.
    problem

    F'arc'tion

    Age
    14 to 16
    Challenge level
    2 out of 3

    At the corner of the cube circular arcs are drawn and the area enclosed shaded. What fraction of the surface area of the cube is shaded? Try working out the answer without recourse to pencil and paper.

  • Bound To Be
    problem

    Bound to Be

    Age
    14 to 16
    Challenge level
    2 out of 3

    Four quadrants are drawn centred at the vertices of a square . Find the area of the central region bounded by the four arcs.

  • Giant Holly Leaf
    problem

    Giant Holly Leaf

    Age
    14 to 16
    Challenge level
    3 out of 3
    Find the perimeter and area of a holly leaf that will not lie flat (it has negative curvature with 'circles' having circumference greater than 2πr).
  • Small pepper seedlings in turquoise pots.
    problem

    Two Circles

    Age
    14 to 16
    Challenge level
    3 out of 3

    Draw two circles, each of radius 1 unit, so that each circle goes through the centre of the other one. What is the area of the overlap?

  • The Pillar of Chios
    problem

    The Pillar of Chios

    Age
    14 to 16
    Challenge level
    3 out of 3

    Semicircles are drawn on the sides of a rectangle. Prove that the sum of the areas of the four crescents is equal to the area of the rectangle.

  • Crescents and triangles
    problem

    Crescents and Triangles

    Age
    14 to 16
    Challenge level
    3 out of 3

    Can you find a relationship between the area of the crescents and the area of the triangle?

  • Small pepper seedlings in turquoise pots.
    problem

    Running Race

    Age
    14 to 16
    Challenge level
    3 out of 3

    Weekly Problem 13 - 2006
    If three runners run at the same constant speed around the race tracks, in which order do they finish?