A magic square has the property that each column, each row and each diagonal add up to the same number. The magic square below is a special one called Ramanujan’s square. Notice that each column, row and diagonal sum to 139. What other combinations of squares add up to 139? Enjoy!
22 | 12 | 18 | 87 |
88 | 17 | 9 | 25 |
10 | 24 | 89 | 16 |
19 | 86 | 23 | 11 |
Solution:
You would write the number 7 20 times.
7, 17, 27, 37, 47, 57, 67, 70, 71, 72, 73, 74, 75, 76, 77 (two here), 78, 79, 87, 97
How many 7s would you write if you wrote the numbers 1 to 1000.
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