How can partitioning help me add two digit numbers?

Part ofMaths and NumeracyNumbers and number processes

Snoot and Fin partition numbers into tens and units to help count plants in their garden.

How can I add two-digit numbers?

Adding two digit numbers can be tricky.

You can make it easier by splitting each number into tens and units.

Splitting numbers apart like this is called partitioning.

Example

21 + 45 = ?

21 is the same as 20 + 1

45 is the same as 40 + 5

So 21 + 45 can be written as 20 + 1 + 40 + 5

Try adding the tens first 20 + 40 = 60

Then add the units 1 + 5 = 6

Then add these together 60 + 6 = 66

Was that easier?

Snoot and Fin count spaceships from the space station.

Which order should I add numbers in?

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