YOU: Let’s add thirty-six and twenty-seven. For thirty-six, we have three bundles of ten toothpicks—that’s thirty—plus six extra toothpicks: the ones. For twenty-seven we have two bundles of ten, plus seven extra ones. How many bundles of toothpicks do we have? CHILD: (Counts the bundles.) Five. YOU: How many toothpicks are in those five bundles all together? CHILD: Fifty. YOU: How many ones—single toothpicks—do we have? CHILD: (Groups the six toothpicks with the seven.) Thirteen. YOU: Can we write thirteen in the ones column? No, because it won’t fit. Where can we put the extra toothpicks?
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