2.2x3.3+3.3x4.4+4.4x5.5 如何简便计算

问题描述:

2.2x3.3+3.3x4.4+4.4x5.5 如何简便计算

2.2x3.3+3.3x4.4+4.4x5.5
=1.1*1.1*(2*3+3*4+4*5)
=1.21*38=

原式=1.1*1.1*6+1.1*1.1*12+1.1*1.1*20
=1.1*1.1*(6+12+20)
=1.1*1.1*38
=1.21*38
=45.98

2.2x3.3+3.3x4.4+4.4x5.5
=1.1x2x1.1x3+1.1x3x1.1x4+1.1x4x1.1x5
=1.1x1.1x(2x3+3x4+4x5)
=1.21x38
=1.21x(40-2)
=1.21x40-1.21x2
=48.4-2.42
=45.98
(这题主要运用乘法分配律.)

楼上正解