Adding and subtracting multiples of 100
Let’s count on by tens from 78.
78
…
Let’s count back by hundreds from 900.
900
…
Use blocks to represent the number 354. Add a block of 100. What do you notice?
Complete the calculation 354 + 100 on a calculator. Continue adding a block of 100 at a time until there are 9 hundreds blocks.
Talk about any patterns you notice. Now subtract a block of 100 at a time until there are none left. What do you notice this time?
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03/05/2022 10:20
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