Grade 5

Read the Headline Story to the students and write the numbers so they can see them. See sample responses for ideas.

The sum of 10 + 10 + 10 can be rewritten as the sum of consecutive numbers: 9 + 10 + 11. How can you use this idea to find consecutive numbers that add up to 45?

- We can make 45 as a sum of equal number. 45 = 5 × 9, or 9 + 9 + 9 + 9 + 9. Then, make the first ones smaller and the later ones larger so that the middle stays the same: 7 + 8 + 9 + 10 + 11.
- We can make 45 as 15 + 15 + 15, so also as 14 + 15 + 16.

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