简便运算 1.13×67+28×33-15×23 2.64.7×0.25+135.3÷4本人（@ .@）(?.)请写解析,让我学习一下

1、13×67+28×33-15×23
=13x67+13x33+15x33-15x23
=13x(67+33)+15(33-23)
=13x100+15x10
=1300+150
=1450
2.64.7×0.25+135.3÷4
=64.7x1/4+135.3x1/47
=(64.7+135.3)x1/4
=200x1/4
=50