1. Copyright Tim Morris/St Stephen's School
Slices of 
This is a series of Powerpoint slideshows to illustrate how to calculate the area of various 2-D shapes.
Start with the Rectangle, then move onto the Parallelogram.
After that select any of Triangle, Trapezium and Circle.
Please feel free to copy and modify any of these slide shows, but make sure you acknowledge the author when doing so.
Copyright Tim Morris/St Stephen's School

2. Copyright Tim Morris/St Stephen's School
Slices of 
Copyright Tim Morris/St Stephen's School

3. Copyright Tim Morris/St Stephen's School
Slices of ½ 
Copyright Tim Morris/St Stephen's School

4. Copyright Tim Morris/St Stephen's School
Slices of ¼ 
Copyright Tim Morris/St Stephen's School

5. Copyright Tim Morris/St Stephen's School
Slices of ¼ 
Copyright Tim Morris/St Stephen's School

6. Copyright Tim Morris/St Stephen's School
Slices of ¼ 
Copyright Tim Morris/St Stephen's School

7. Copyright Tim Morris/St Stephen's School
Slices of ¼ 
Copyright Tim Morris/St Stephen's School

8. Copyright Tim Morris/St Stephen's School
Slices of ¼ 
Copyright Tim Morris/St Stephen's School

9. Slices of ¼  Total distance along the top = ½ circumference
Copyright Tim Morris/St Stephen's School

10. Slices of ¼  Total distance along the top = ½ circumference
Length of side = radius
Copyright Tim Morris/St Stephen's School

11. Copyright Tim Morris/St Stephen's School
Slices of 1/8 
Copyright Tim Morris/St Stephen's School

12. Copyright Tim Morris/St Stephen's School
Slices of 1/8 
Copyright Tim Morris/St Stephen's School

13. Copyright Tim Morris/St Stephen's School
Slices of 1/8 
Copyright Tim Morris/St Stephen's School

14. Copyright Tim Morris/St Stephen's School
Slices of 1/8 
Copyright Tim Morris/St Stephen's School

15. Copyright Tim Morris/St Stephen's School
Slices of 1/8 
Copyright Tim Morris/St Stephen's School

16. Copyright Tim Morris/St Stephen's School
Slices of 1/8 
Copyright Tim Morris/St Stephen's School

17. Copyright Tim Morris/St Stephen's School
Slices of 1/8 
Copyright Tim Morris/St Stephen's School

18. Copyright Tim Morris/St Stephen's School
Slices of 1/8 
Copyright Tim Morris/St Stephen's School

19. Copyright Tim Morris/St Stephen's School
Slices of 1/8 
Copyright Tim Morris/St Stephen's School

20. Slices of 1/8  Total distance along the top = ½ circumference
Copyright Tim Morris/St Stephen's School

21. Slices of 1/8  Total distance along the top = ½ circumference
Length of side = radius
Copyright Tim Morris/St Stephen's School

22. Copyright Tim Morris/St Stephen's School
Slices of 1/16 
Copyright Tim Morris/St Stephen's School

23. Copyright Tim Morris/St Stephen's School
Slices of 1/16 
Copyright Tim Morris/St Stephen's School

24. Copyright Tim Morris/St Stephen's School
Slices of 1/16 
Copyright Tim Morris/St Stephen's School

25. Copyright Tim Morris/St Stephen's School
Slices of 1/16 
Copyright Tim Morris/St Stephen's School

26. Copyright Tim Morris/St Stephen's School
Slices of 1/16 
Copyright Tim Morris/St Stephen's School

27. Copyright Tim Morris/St Stephen's School
Slices of 1/16 
Copyright Tim Morris/St Stephen's School

28. Copyright Tim Morris/St Stephen's School
Slices of 1/16 
Copyright Tim Morris/St Stephen's School

29. Copyright Tim Morris/St Stephen's School
Slices of 1/16 
Copyright Tim Morris/St Stephen's School

30. Copyright Tim Morris/St Stephen's School
Slices of 1/16 
Copyright Tim Morris/St Stephen's School

31. Copyright Tim Morris/St Stephen's School
Slices of 1/16 
Copyright Tim Morris/St Stephen's School

32. Copyright Tim Morris/St Stephen's School
Slices of 1/16 
Copyright Tim Morris/St Stephen's School

33. Copyright Tim Morris/St Stephen's School
Slices of 1/16 
Copyright Tim Morris/St Stephen's School

34. Copyright Tim Morris/St Stephen's School
Slices of 1/16 
Copyright Tim Morris/St Stephen's School

35. Copyright Tim Morris/St Stephen's School
Slices of 1/16 
Copyright Tim Morris/St Stephen's School

36. Copyright Tim Morris/St Stephen's School
Slices of 1/16 
Copyright Tim Morris/St Stephen's School

37. Copyright Tim Morris/St Stephen's School
Slices of 1/16 
Copyright Tim Morris/St Stephen's School

38. Copyright Tim Morris/St Stephen's School
Slices of 1/16 
Copyright Tim Morris/St Stephen's School

39. Slices of 1/16  Total distance along the top = ½ circumference
Copyright Tim Morris/St Stephen's School

40. Slices of 1/16  Total distance along the top = ½ circumference
Length of side = radius
Copyright Tim Morris/St Stephen's School

41. Copyright Tim Morris/St Stephen's School
Slices of 1/… 
And if I had time to create a pie with many, many more slices than 16, maybe 32, or 64, or 128 or even more slices than any other power of 2 (which all these numbers are), then I would end up with a pie with an infinite () number of red and yellow slices which when sliced up would look more and more like a rectangle as the top and bottom edges become less wavy and the sides become more vertical…
Copyright Tim Morris/St Stephen's School

42. Copyright Tim Morris/St Stephen's School
Slices of 1/ 
Copyright Tim Morris/St Stephen's School

43. Slices of 1/  Total distance along the top = ½ circumference
Copyright Tim Morris/St Stephen's School

44. Slices of 1/  Total distance along the top = ½ circumference
Length of side = radius
Copyright Tim Morris/St Stephen's School

45. Copyright Tim Morris/St Stephen's School
Slices of 1/
Total distance along the top = ½ circumference ½ circumference = ½ (2   radius)
Length of side = radius
Copyright Tim Morris/St Stephen's School

46. Slices of 1/
Total distance along the top = ½ circumference ½ circumference = ½ (2   radius)
Area = Top distance x Length of side
Length of side = radius
Copyright Tim Morris/St Stephen's School

47. Slices of 1/
Total distance along the top = ½ circumference ½ circumference = ½ (2   radius)
Area = ½ (2    radius)  radius
Length of side = radius
Copyright Tim Morris/St Stephen's School

48. Slices of 1/
Total distance along the top = ½ circumference ½ circumference = ½ (2   radius)
Area =   radius  radius
Length of side = radius
Copyright Tim Morris/St Stephen's School

49. Copyright Tim Morris/St Stephen's School
Slices of 1/
Total distance along the top = ½ circumference ½ circumference = ½ (2   radius)
Area =   radius2
Length of side = radius
Copyright Tim Morris/St Stephen's School