(10-3/55×1)+(9-3/55×2)+(8-3/55×3)+……+(2-3/55×9)+(1-3/55×10)=?
问题描述:
(10-3/55×1)+(9-3/55×2)+(8-3/55×3)+……+(2-3/55×9)+(1-3/55×10)=?
(10-3/55×1)+(9-3/55×2)+(8-3/55×3)+……+(2-3/55×9)+(1-3/55×10)=?
答
原式=10+9+8.+1-3/55×(1+2+3.+10)
=55-3/55×55
=55-3
=52