Keep the gap | One for ten | ABC of Mathematics

ABC of Mathematics

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Math › Invent Arithmetic › One for ten

Break it up Parts in boxes Break up again

The short way Each total in full In your head, from the left Make one number round

Any order you like Pair them up Always, or only sometimes?Name the move

One for ten Where are the ones?Trade on paper Keep the gap Do the laws hold?

Rows of pebbles Count the tray Laws of times Count on Fill the table

Cut the rectangle Times ten Cut the tray Times one digit On paper

Crosswise Four pieces Level by level More digits Carry as you go

Double it A table of doubles Double and add Every number?

The fair Check the bill Set a price Lunchtime Close the box

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