2099
Well, 1 is equal to 1. 9 is equal to 9. So any number from 0 to 9. I do not think this is what is meant by the question. If you mean any number with more than one digit. There is no such number. Because 11 sums to 2. 19 sums to 10. 21 sums to 3. 29 sums to 11. 111 sums 3. 119 sums to 11. The sums do not grow as fast the increase of digits.
97, for example.
The Riots
Digits: 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9. The sum of all digits is 45.
10p is not a digit. A digit is an integer in the range 0-9. Leaving that aside, you can make 31 sums from the 5 coins. If you allow 0 as a valid sum, the answer is 32.
The basic idea is the same as when you estimate sums and differences of larger numbers (which may or may not be integers). You round the numbers to one or two decimal digits, then add them up.
1+8=9, 9x2=18 so 18 is one answer to this problem
556 + 323 = 879 whose digits sum to 24.
Step by step and following the mathematical instructions as given by the expression.
If you are thinking of a mgic square, the answer is NO. The nine numbers sum to 45 so if you have three rows with equal sums, that sum can only be 45/3 = 15. You can have two rows, each adding to 17, and using the digits only once, but you will not use all digits.
2 + 3 = 5
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