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I have fifteen cards numbered $1 - 15$.
I put down seven of them on the table in a row.
The numbers on the first two cards add to $15$.
The numbers on the second and third cards add to $20$.
The numbers on the third and fourth cards add to $23$.
The numbers on the fourth and fifth cards add to $16$.
The numbers on the fifth and sixth cards add to $18$.
The numbers on the sixth and seventh cards add to $21$.
What are my cards?
Can you find any other solutions?
How do you know you've found all the different solutions?
An investigation involving adding and subtracting sets of consecutive numbers. Lots to find out, lots to explore.
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