7.8×99+9.9×22简便计算

Question

如题所述

Answer 1

7.8×99+9.9×22简便计算，
7.8*99+9.9*22
=7.8*99+2.2*99
=(7.8+2.2)*99
=10*99
=990

Answer 2

7.8×0点99+9点九 =7.8×0.99+0.99×10 =0.99×(7.8+10) =(1-0.01)×17.8 =17.8-0.178 =17.622。

Answer 3

7.8×99+3.9×2的简便计算 7.8×99+3.9×2 =7.8x99+7.8 =7.8x99+7.8x1 =7.8x（99+1） =7.8x100 =780

Answer 4

7.8×99+9.9×22
=99x(7.8+2.2)
=99x10
=990

Answer 5

=99*(7.8+2.2)=990本回答被提问者采纳