9.9*7.6 99*0.24 怎么简便
问题描述：
9.9*7.6 99*0.24 怎么简便
答
9.9×7.6
=(10-0.1)×7.6
=10×7.6-0.1×7.6
=76-0.76
=75.24
99×0.24
=(100-1)×0.24
=100×0.24-0.24
=24-0.24
=23.76