能简便的用简便方法计算. 6.28*3.7+62.8*0.63 = 5/7+1/3*9+4/13 =

问题描述:

能简便的用简便方法计算. 6.28*3.7+62.8*0.63 = 5/7+1/3*9+4/13 =

原式=6.28*3.7+6.28*10*0.63=6.28(3.7*10*0.63)=6.28*10=62.8
原式=5/7+3+4/13= 3+45/91+28/91=3又73/91