Primary 6 · Circle · Question type 6.3
The perimeter of a semicircle or quarter circle includes both the arc and the new straight edges.
Try the question yourself, or watch the lesson first.
Primary 6, on the MOE Primary Mathematics syllabus.
The lesson · 3 minutes 1 second
Watch: the perimeter of a semicircle, then of a quarter circle
Another worked example
A pizza has a 3/4 piece left, cut from its centre. The piece has a radius of 10 cm. Find the perimeter of the piece. (Take π = 3.14.)
The working · Four lines
Written out in full, the way it should appear on paper.
The answer is 67.1 cm.
Practise · Modelled on top school exam questions
Try it yourself first. Open the solution when you want to see the steps. No sign-up is needed. These questions are written by Mathweave, not copied from school papers.
Try it yourself
Include the curved edge and both straight radii, leaving the answer in terms of pi.
A quarter circle has a radius of 8 cm. Find the perimeter of the quarter circle, leaving your answer in terms of π.
Try it yourself first. Then open the solution to compare your answer and working.
Ans: (4π + 16) cm
The practice plan adds more questions and saved progress.
Next, exclude the joined edge inside a composite figure. Perimeter of a Rectangle with a Semicircle →