1+3又1/6+5又1/12+7又1/20+9又1/30+11又1/42等于多少?
问题描述:
1+3又1/6+5又1/12+7又1/20+9又1/30+11又1/42等于多少?
答
1+3又1/6+5又1/12+7又1/20+9又1/30+11又1/42=1+3+5+7+9+11+1/6+1/12+1/20+1/30+1/42=(1+11)x6÷2+(1/2-1/3)+(1/3-1/4)+(1/4-1/5)+(1/5-1/6)+(1/6-1/7)=36+1/2-1/7=36+5/14=36又5/14