99.99×77.78+33.33×66.66,能不能简便算吗?怎么算?

问题描述:

99.99×77.78+33.33×66.66,能不能简便算吗?怎么算?

原式=99.99×77.78+33.33×66.66 =99.99×77.78+99.99×22.22 =99.99×(77.78+22.22) =99.99×100 =9999