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Why Do the Diagonal Sums Match in a Number Grid?

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Expressions using Letter-Numbers · Calendar and number-grid relationships · 3:17

You'll learn: Using a letter for one corner shows both diagonal sums are always equal.

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Why Do the Diagonal Sums Match in a Number Grid?

3:17

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Why Do the Diagonal Sums Match in a Number Grid?

You'll learn: Using a letter for one corner shows both diagonal sums are always equal.

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