减法的性质639851563985156398515例:63985156398515273(17318)试一试:47-32+22 47-(32-22)=15+22=3747-32+22=47-(32-22)=47-10=3726-(16-4)=26-12=1426-16+4=10+4=1426-(16-4)=26-16+4454-155+45=454-()155-45454-155-45=454-()155+4578-(28-15)=78 78-(28+15)=78 -28+15-28-151193 1114(165)14(93)165填一填189-53+23=189+53+47=514+(36-19)=435-(235-19)=189-(53-23)189+(53+47)514+36-19435-235+192847-(847+629)=753-463-153=38-(15+18)=456+78-56=填一填用简便方法计算265-37-63172-(72+85)96-(46-13)239+85-15241+(59-27)803-132-168下面各题哪些能用简便方法计算?147-76-24 425-263-63 147-26+74 96-(18+26)93+24+7 54+39-29