999
1998
999 + 9999999999 + 9999999999 + 8888888 = 20,008,889,885
333 + 999 = 1332
999 + 781 = 1780
399 + 999 + 4999 + 899 + 999 + 599 + 899 + 1499 + 4499 + 100 = 15891
1499 + 280 = 1779
Oh, dude, 999 plus 999 is like totally 1998... just kidding, it's 1998. Like, you're basically adding two nines together to get 18, then slapping another nine on there for a grand total of 1998. Math, man, it's wild.
999
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