0.45x5.5+0.55x4.5+0.55(递等式计算)巧算

问题描述:

0.45x5.5+0.55x4.5+0.55(递等式计算)巧算

0.45x5.5+0.55x4.5+0.55
=4.5×0.55+0.55x4.5+0.55
=0.55×(4.5+4.5+1)
=0.55×10
=5.5