1. LO: to add decimals Type your name and send: Next Slide

2. The Basic Steps: Line up the numbers by the decimal point. Fill in missing places with zeroes. Add or subtract. Next Slide

3. Addition Properties Commutative Property of Addition: Numbers can be added in any order. Example: 5+3=3+5 Associative Property of Addition: Numbers can be grouped in any way. Example: (7+3) + 5 = 7 + (3+5) Next Slide

4. Find the nearest nice number Addition properties can be used to quickly find sums. Example: What is 52 + 12.4 + 48? We can use an addition property to quickly add this. First, change the order: 52 + 48 + 12.4 ________________ property. Then, group the easy numbers together: (52 + 48) + 12.4 ________________ property 100 + 12.4 = 112.4 commutative associative Next Slide

5. Why Estimate? Before adding your numbers, use one of the estimating strategies you learned to see what the answer should be close to. When you add, you can see if your answer is reasonable. Next Slide

6. Example: 28.9 + 13.31 28.9 13.31+ 0 42.21 Line up the numbers by the decimal point. Fill in missing places with zeroes. Add or subtract. This can estimate to 30 + 13, which is 43. (nearest nice numbers) The answer is close to the estimate. Next Slide

7. Now your turn. For the sum: 125.33 + 6.9 What would your estimate be? a)118 b)132 c)131 Next Slide

8. For the sum: 125.33 + 6.9 {estimate is 132} Which number should you write first? a)125.33 b)6.9 c)It does not matter Next Slide

9. For the sum: 125.33 + 6.9 {estimate is 132} I write down 125.33 what do I do next? Line up the numbers by the decimal point. Fill in missing places with zeroes. Add or subtract. Next Slide

10. For the sum: 125.33 + 6.9 {estimate is 132} What do you need to do now? 125.33 6.9+ A.Add B.Subtract C.Stick zero in if you have any gaps 0 Next Slide

11. For the sum: 125.33 + 6.9 {estimate is 132} What do you need to do now? 125.33 6.90+ A.Add B.Subtract C.Stick a decimal in underneath then relax Next Slide

12. For the sum: 125.33 + 6.9 {estimate is 132} Finally add to give the answer? 125.33 6.90+ Next Slide

13. For the sum: 125.33 + 6.9 {estimate is 132} Finally add to give the answer? 125.33 6.90+ 132.23 Is this near to your estimate? Next Slide

14. I really understand this and I got most of them correct. I am beginning to understand this and I got many of them correct. I need more practice to help me understand this and I made lots of mistakes. A B C LO: to add with decimals. Last Slide