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TUTORIAL 3Read about basic facts from pp 206-224 (Reys) and discuss question 1-6 in page 226. Summarise all the strategies for teaching basic facts.What properties of addition and multiplication are especially helping in teaching the basic facts

MULTIPLICATIONCOMMUTATIVITYChanging the order of the addends does not affect the sumExample: 2+5= 2or 5+ 5+2 7 7

STRATEGIES FOR ADDING ONE AND ADDING ZEROExample: adding 1 or adding 0

1 +1 keep on using 1 +0keep on using 2 +1 without changing 2 +0without changing3 +1 the number 3 +0the numberATRATEGIES FOR ADDING DOUBLES AND NEAR DOUBLESDoubles are basic facts in which both addends are the same numberExample: 4+4= 3+3= 2+2=Can change the numberCan change the numberNear doubles can be used for the facts that are one more or one less than the doublesExample: 7+8= (7+7==14), must add more 1 to get of the answer or (8+8=16), must substract 1 to get the answer.COUNTING ONUse for any addition facts but is most easily used when one of the addends is 1, 2 or 3To be efficient, it is important to count on from the larger addendExample 2+6=86+2=2+6

ADDING TO 10 AND BEYOND One addend is increased and the other decreased, to make one of the addends 10Example: 8+5=8+2=3+10=13, so 8+5=13628MULTIPLICATIONCOMMUTATIVITYCan multiply 46 or 6 4 for example, and realize that the answer to both is 24Skip counting4 5= (skip 4 timesREPEATED ADDITIONCan be used most efficiently when one of the factors is less than 5Example: 3 6=Example: 3 5=2 5=1010+5=15Thus, 3 5=15USING 0 OR 1Need to be able to generalize that multiplying with 1 does not change the other number and that multiplying by 0 will give 0 as the product.