(1+2+ 3+•••+99+100)×12345=?
问题描述:
(1+2+ 3+•••+99+100)×12345=?
答
(1+100)*100/2*12345=5050*12345=62342250
(1+2+ 3+•••+99+100)×12345=?
(1+100)*100/2*12345=5050*12345=62342250