1.125+2.125+3.125+.80.125等于多少?
问题描述:
1.125+2.125+3.125+.80.125等于多少?
答
=(1+2+3+...+80)+(1/8+1/8+...+1/8) 80个1/8
=(1+80)×80÷2+10
=3250