递等式计算:48×0.25×1.25=?简便计算
问题描述：
递等式计算:48×0.25×1.25=?简便计算
答
48×0.25×1.25
=(40+8)×0.25×1.25
=40×0.25×1.25 +8×1.25×0.25
=10×1.25 +10×0.25
=12.5 +2.5
=15