1.用简便方法计算:33乘66+33乘6-33乘2 103乘25 96乘125 42乘(20+5)用递等式计算.(本人没分了)

问题描述:

1.用简便方法计算:33乘66+33乘6-33乘2 103乘25 96乘125 42乘(20+5)用递等式计算.(本人没分了)

33×66+33×6-33×2
=33(66+6-2)
=33×70
=30×70+3×70
=2100+210
=2310
103×25
=100×25+4 ×25-25
=2500+100-25
=2575
96×125
=8×12×125
=8×125 ×12
=1000×12
=12000
42×(20+5)
=42×25
=40×25+2×25
=1000+50
=1050