99×8.13 3.49×2.71-0.49×2.71的简便运算？

Question

如题所述

Answer 1

99×8.13+3.49×2.71-0.49×2.71
=99x8.13+2.71x（3.49-0.49）
=99x8.13+2.71x3
=99x8.13+8.13
=（99+1）x8.13
=100x8.13
=813

Answer 2

运用乘法分配律
99×8.13
=（100-1）×8.13
=100×8.13-1×8.13
=813-8.13
=804.87
3.49×2.71-0.49×2.71
=（3.49-0.49）×2.71
=3×2.71
=8.13