1 / 4

Near Doubles

Near Doubles. I am learning to solve addition problems where the two numbers are easily related to doubles. e.g. 9 + 9 = 18 Or 80 + 80 = 160. Craig has $79 and saves another $81. How much money does he have?. 79 + 81 = ?. Step 1: Let’s use some notes and coins to represent this question.

selene
Download Presentation

Near Doubles

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. Near Doubles I am learning to solve addition problems where the two numbers are easily related to doubles. e.g. 9 + 9 = 18 Or 80 + 80 = 160

  2. Craig has $79 and saves another $81. How much money does he have? 79 + 81 = ? Step 1: Let’s use some notes and coins to represent this question. Step 2: If we move $1 from the $79 to the $80 then both piles will have $80. Step 3: Swap the ten $1 coins for a $10 note and then both groups have $80 80 + 80 = 160 $10 $10 $10 1 1 $10 $10 $10 1 1 $10 $10 1 $10 1 $10 $10 $10 1 1 $10 $10 1 $10 1 $10 1

  3. Kim drove 78km on Monday and 79km on Tuesday. How many kilometres has she driven? 78 + 79 = ? Step 1: Let’s use our doubles to help us answer this question. Change the question into 80 + 80. This will be much easier to answer. 78 + 79 = …… +2 +1 80 + 80 = 160 Step 2: We added 2 to the 78 and 1 to the 79 (a total of 3). So now we must subtract 3 from our answer of 160. 160 – 3 = 157

  4. Now try these questions on your own. • 69 + 71 = ? • 38 + 38 = ? • 89 + 92 = ? • 148 + 252 = ? • 119 + 119 = ? 140 Click again when you have completed each question and the answer will be displayed. 76 181 400 238 Need some more practise? Try Pg55 of Teacher Tools Addition and Subtraction Book Numeracy resources

More Related