999 plus 999 = 1998
1998
999
999 + 9999999999 + 9999999999 + 8888888 = 20,008,889,885
999 + 12,345 is 13,344.
999 + 36 = 1035
333 + 999 = 1332
999 + 781 = 1780
999 + 99 = 1098
999 999
999 trillion plus 99.9 billion is 999,099,900,000,000
The sum of 999 and 1,110 is 2,109.