2+4+6+...+100等于多少?
问题描述:
2+4+6+...+100等于多少?
(1/2+1/3+1/4)/(1/2x1/3x1/4)
答
(2+100)*(50/2)=2550
(1/3*1/4)+(1/2*1/4)+(1/2*1/3)=3/8