You can put this solution on YOUR website! Let's break the number 9173 down into parts...
4500 + 4500 = 9000...leaving 173 to go
85 + 85 = 170...leaving 3 to go
1 + 2 = 3...leaving 0 to go
So add up in a vertical formation...
4500 + 85 + 1 = 4586
4500 + 85 + 2 = 4587
Those are your two consecutive numbers that add up to 9173 :)