Tis Unique
| * | * | 4 | |
| + | 2 | 8 | * |
| * | * | * | * |
This addition sum uses all ten digits 0, 1, 2 ...9 exactly once. Find the sum and show that the one you give is the only possibility.
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Choose any 3 digits and make a 6 digit number by repeating the 3 digits in the same order (e.g. 594594). Explain why whatever digits you choose the number will always be divisible by 7, 11 and 13.
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