2.1÷1.7×5.1÷159.1×3.7÷0.7.

问题描述:

2.1÷1.7×5.1÷159.1×3.7÷0.7.

2.1÷1.7×5.1÷159.1×3.7÷0.7,
=(2.1÷0.7)×(5.1÷1.7)÷(159.1÷3.7),
=3×3÷43,
=9÷43,
=

9
43