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Mathematics: a garden of numbers · Lesson 02 / 06

Add, take away and check

The garden’s stock changes: seeds arrive and some are planted. Let’s follow each change.

Learning paths6 min

Let's discover together

  1. 1

    Addition can represent combining: 7 seeds plus 5 seeds. To reach ten, add 3 of the 5; then add the remaining 2.

  2. 2

    Subtraction can represent taking away. Use the total present at that moment, not just the initial amount.

  3. 3

    To check a subtraction, combine what remains with what was removed. You should recover the previous total.

✦
YOUR MISSION

Solve an addition and a subtraction and check with the inverse operation.

Now it's your turn

Discovery workshop

Add, take away and check

There were 7 seeds. Another 5 arrived. Then Lia planted 4 seeds from that total.
Build your answers and check when you are ready.
A moment to understand

Which calculation checks the subtraction?

I need a hint

Combine what remained with what was planted.

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Take it with you

Invent another arrival-and-removal story. Draw the amounts and write a calculation to check it.

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