June 2020 - Math Problem

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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