1.125+2.125.+3.125+4.125+5.125+……+50.125=

问题描述:

1.125+2.125.+3.125+4.125+5.125+……+50.125=

1.125+2.125.+3.125+4.125+5.125+……+50.125 =(1+2+3+...+50)+0.125×50 =1275+6.25 =1281.25