12.5x79+12.5x2-12.5简便算法
问题描述:
12.5x79+12.5x2-12.5简便算法
答
=12.58*(79+2-1)
答
12.5x79+12.5x2-12.5
=12.5*(80-1)+12.5*(2-1)
=125*8-12.5+12.5
=1000
答
12.5x79+12.5x2-12.5
=12.5x(79+2-1)
=12.5x80
=1000