(10-55\4*1) +(9-55\4*2)+(8-55\4*3)+……+(1-55\4*10)=?快

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(10-55\4*1)+(9-55\4*2)+(8-55\4*3)+……+(1-55\4*10)=?快(10-55\4*1)+(9-55\4*2)+(8-55\4*3)+……+(1-55\4*10)=

(10-55\4*1) +(9-55\4*2)+(8-55\4*3)+……+(1-55\4*10)=?快
(10-55\4*1) +(9-55\4*2)+(8-55\4*3)+……+(1-55\4*10)=?

(10-55\4*1) +(9-55\4*2)+(8-55\4*3)+……+(1-55\4*10)=?快
原式=10+9+8+……+1-4/55*(1+2+3+……+10)
=(1+2+3+……+10)(1-4/55)
=[(10+1)×10/2]*51/55
=55*51/55
=51