Q1. If the total spending is $60, what is the value of one degree?
✔ Divide the total amount by three hundred sixty degrees to find the value per degree.
Q2. Siti spent $18 on food which is one hundred eighty degrees. What was the total budget?
✔ One hundred eighty degrees is half of three hundred sixty, so double the food cost.
Q3. Which step is incorrect when solving pie chart problems?
✔ You should add parts to check the total, not subtract total from a single part.
Show transcript
[Slide 1] Understanding Pie Charts
Welcome class. Today we learn how to solve money problems using pie charts. Think of a pizza shared among friends at a hawker centre.
[Slide 2] The Bar Model Method
We use the bar model to visualise the parts clearly. First, find the value represented by each degree. Then multiply by the specific angle needed.
[Slide 3] Example at Tampines Hawker Centre
Siti and Mei Ling spent forty dollars on lunch and travel. Their pie chart shows food costs more than transport. Let us find out exactly how much they spent on food.
[Slide 4] Solving the Calculation
Divide forty dollars by three hundred sixty to find one degree. Then multiply that value by two hundred seventy degrees. The answer is thirty dollars for their delicious meal.
[Slide 5] Common Mistake Alert
Many students forget to find the value of one degree first. Always check if your parts add up to the whole. This ensures your calculation is accurate and complete.
[Slide 6] Key Takeaways Recap
Remember that a full circle is three hundred sixty degrees. Link the angles to money using simple division and multiplication. You are now ready for your PSLE pie chart questions.