Q2. If the radius is 3 metres, what is the area? (Use pi = 3.14)
✔ Calculate 3.14 times 3 squared, which is 3.14 times 9.
Q3. Wei Ming has a circular table with diameter 10 cm. What is the radius?
✔ Radius is half of the diameter, so divide 10 by 2.
Show transcript
[Slide 1] Visualising Circle Area
Think of a round table at a hawker centre. If we cut it into sectors, they form a rectangle. This helps us understand the area formula intuitively.
[Slide 2] The Area Formula
Remember to use the radius, not the diameter. Always square the radius before multiplying by pi. This rule applies to all circles.
[Slide 3] Siti's Round Mat
First, calculate the area of the circular mat. Then multiply by the cost to find the total price. Visualise the total cost as bars representing each square metre unit.
[Slide 4] Watch Out For Errors
Many students forget to divide diameter by two first. Others multiply pi by radius instead of squaring it. Always check which measurement is given.
[Slide 5] Key Takeaways
You now know how to find circle area. Use this for PSLE questions on circles. Keep practising with different contexts.