1. 999 + 1 = 10002. 500 + 500 = 10003. 100 + 900 = 10004. 2 + 998 = 10005. 1 + 999 = 10006. 888 + 88 + 8 + 8 + 8 = 10007. 888 + 88 + 8 + 8 + 8 = 10008
