1 / 14

LO: to add decimals

Next Slide. LO: to add decimals. Type your name and send:. The Basic Steps:. Next Slide. Line up the numbers by the decimal point. Fill in missing places with zeroes. Add or subtract. Addition Properties. Next Slide. Commutative Property of Addition: Numbers can be added in any order.

dawn-coleman
Download Presentation

LO: to add decimals

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

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

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

  3. Addition Properties Next Slide 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)

  4. Find the nearest nice number Next Slide • 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

  5. Why Estimate? Next Slide • 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.

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

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

  8. For the sum: 125.33 + 6.9 {estimate is 132} Which number should you write first? 125.33 6.9 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? Next Slide • Line up the numbers by the decimal point. • Fill in missing places with zeroes. • Add or subtract.

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

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

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

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

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

More Related