Question

31✖️870➕13✖️310简便算法？

Answer 1

31✖️870➕13✖️310

=310×87+13×310......................根据积的变化规律找因数310

=310×（87+13）....................乘法的分配律

=310×100

=31000

Answer 2

31×870+13×310
=31×87×10+310×13
=310×87+310×13
=310×(87+13)=310×100=31000
希望能帮到你。

Answer 3

87×31+84-23