← Near Enough · Lesson 2 of 4
Make a ten
Adding is easier when you land on a ten. For 8 + 7, move 2 from the 7 to the 8: that makes 10 + 5, which is 15.
The same move works on bigger numbers. For 38 + 27, give 2 of the 27 to the 38 to make 40. That leaves 25 to add: 65.
Use make-a-ten: what is 38 + 27?
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