Addition Symbols Problems Where can we put addition symbols between digits of the number 987654321 to get an expression that has a total of exactly 99? Where can we put addition symbols between digits of the number 123456789 to get an expression that has a total of exactly 99? Solution There are a few solutions for each of the two problems. 1. One solution for the first problem is to put the addition symbols after the 9, 8, 7, 6, 5, 3, and 1. The resulting equation will be: 9 + 8 + 7 + 6 + 5 + 43 + 21 = 99 2. One solution for the second problem is to put the addition symbols after the 1, 3, 5, 6, 7, 8, and 9. The resulting equation will be: 1 + 23 + 45 + 6 + 7 + 8 + 9 = 99