My strategy to solve this problem

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     26 + 44 =  70

    /   \    /   

           20  +  6  + 4 = 10   20 + 50 = 70

                                       

I know that 26 has 2 tens + 6 ones. The 6 ones needs 4 more ones to make a tidy ten. So 20+10=30.From 30 I now need to get to 70.I know that 30 + 40 =70. So 40 + 4 =44.The answer The answer is 26+ 44=70.