Level 3
In the figure, not drawn to scale, O is the centre of the circle. Given that the ratio of ∠OBC : ∠AOC is 3 : 11. Find ∠AOB.
4 m
Level 3
In the figure, not drawn to scale, O is the centre of the smaller circle. AB is a straight line. Find ∠AED.
4 m
Level 3 PSLE
The figure shows a rectangular grass patch and an L-shaped footpath. The width of the footpath is 100 cm. The footpath is tiled using 38 circular tiles of diameter 50 cm, following the pattern shown. Each tile is in contact with those next to it.
  1. What is the area of the footpath not covered by the tiles? Take π = 3.14.
  2. What is the perimeter of the grass patch?
4 m
Level 3
The figure is not drawn to scale. Two balls, X and Y, turn and move along the line AB in opposite directions. The radius of X is 10 cm. The ratio of the diameter of Ball X to that of Ball Y is 5 : 2. If Ball X turns 10 rounds and Ball Y turns 2 rounds, how far apart are the centres of the balls? (Take π = 3.14)
4 m
Level 3
The figure shows 4 similar right-angled triangles arranged to form a big square which encloses a circle. The midpoints of the 4 sides of the big square touch the circumference of the circle. The two sides which form the right angle of each triangle are 16 cm and 12 cm respectively. Find the area of the shaded part. (Take π = 3.14)
4 m