The relationship between addition and subtraction
We can use part-whole relationships to think about addition and subtraction. Talk to your partner about how you can use the bar model to show that:
75
25
100
75 + 25 = 100 25 + 75 = 100
100 − 25 = 75 100 − 75 = 25
Leon has nine shells in his bucket. He collects some more shells from a rock pool and puts them in his bucket.
Use cubes and counters to act out what happens with the shells in Leon’s bucket. Find different ways to make the story true. What do you notice about the number of shells in the bucket at the start of the story and the number in the bucket at the end of the story? Can you explain why?
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04/05/2022 15:49
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