(-1又1/2)+(-6.25)+3又1/8)+(-1.75)+2又3/8=多少?
问题描述:
(-1又1/2)+(-6.25)+3又1/8)+(-1.75)+2又3/8=多少?
答
=-1又1/2-6.25+3又1/8-1.75+2又3/8
=-1又1/2-(6.25+1.75)+(3又1/8+2又3/8)
=-1又1/2-8+5又1/2
=(5又1/2-1又1/2)-8
=4-8
=-4