1. Fractions This presentation will help you to: add subtract
multiply and
divide fractions

2. Adding fractions
To add fractions together the denominator (the bottom bit) must be the same.
Example

3. Adding fractions
To add fractions together the denominator (the bottom bit) must be the same.
Example

4. Adding fractions
To add fractions together the denominator (the bottom bit) must be the same.
Example

5. Now try these
Click to see the next slide to reveal the answers.

6. Now try these

7. Subtracting fractions
To subtract fractions the denominator (the bottom bit) must be the same.
Example

8. Subtracting fractions
To subtract fractions the denominator (the bottom bit) must be the same.
Example

9. Subtracting fractions
To subtract fractions the denominator (the bottom bit) must be the same.
Example

10. Now try these
Click on the next slide to reveal the answers.

11. Now try these .

12. Multiplying fractions
To multiply fractions we multiply the tops and multiply the bottoms
Top x Top
Bottom x Bottom

13. Multiplying fractions
Example

14. Multiplying fractions
Example

15. Multiplying fractions
Example

16. Now try these
Click on the next slide to reveal the answers.

17. Now try these .

18. Dividing fractions
Once you know a simple trick, dividing is as easy as multiplying!
Turn the second fraction upside down
Change the divide to multiply
Then multiply!

19. Dividing fractions
Example
Turn the second fraction upside down

20. Dividing fractions Example Turn the second fraction upside down
Change the divide into a multiply

21. Dividing fractions Example Turn the second fraction upside down
Change the divide into a multiply
Then multiply

22. Dividing fractions Example Turn the second fraction upside down
Change the divide into a multiply
Then multiply

23. Now try these
Click on the next screen to reveal the answers.

24. Now try these

25. Common denominators
To add or subtract fractions together the denominator (the bottom bit) must be the same.
So, sometimes we have to change the bottoms to make them the same.
In “maths-speak” we say we must get common denominators

26. Common denominators 1. Multiply the bottoms together.
To get a common denominator we have to:
1. Multiply the bottoms together.
2. Then multiply the top bit by the correct number to get an equivalent fraction

27. Common denominators
For example

28. Common denominators
For example
Multiply the bottoms together

29. Common denominators
For example
2. Write the two fractions as sixths

30. Common denominators For example
To get ½ into sixths we have multiplied the bottom (2) by 3. To get an equivalent fraction we need to multiply the top by 3 also

31. Common denominators For example
To get ½ into sixths we have multiplied the bottom (2) by 3. To get an equivalent fraction we need to multiply the top by 3 also

32. Common denominators For example
To get 1/3 into sixths we have multiplied the bottom (3) by 2. To get an equivalent fraction we need to multiply the top by 2 also

33. Common denominators For example
To get 1/3 into sixths we have multiplied the bottom (3) by 2. To get an equivalent fraction we need to multiply the top by 2 also

34. Common denominators
For example
We can now rewrite

35. Common denominators
For example
We can now rewrite

36. Common denominators
For example
We can now rewrite

37. Common denominators
For example
We can now rewrite

38. Common denominators
This is what we have done:
1. Multiply the bottoms

39. Common denominators This is what we have done: 2.Cross multiply
1. Multiply the bottoms

40. Common denominators This is what we have done: 2.Cross multiply
1. Multiply the bottoms

41. Common denominators This is what we have done: 2.Cross multiply
1. Multiply the bottoms

42. Now try these
Click on the next slide to reveal the answers.

43. Now try these

44. For further info Go to: BBC Bitesize Maths Revision site
by clicking here: