45乘12乘58减12乘3怎么做最简便
问题描述:
45乘12乘58减12乘3怎么做最简便
答
原式=12x【45x(60-2)-3】 =12x(45x60-45x2-3) =...........
答
45X12X58-12X3
=12(45X58-3)
=12(45X50+45X8-3)
=12(2250+360-3)
=12X2607
=2607X10+2607X2
=26070+5214
=31284