2.1×5.1×159.1÷0.7÷1.7÷3.7(简便计算)
问题描述:
2.1×5.1×159.1÷0.7÷1.7÷3.7(简便计算)
急用!
我们还没学分数乘除法呢,这种题可以简便计算的!
答
2.1×5.1×159.1÷0.7÷1.7÷3.7
=3×0.7×3×1.7×43×3.7÷(0.7×1.7×3.7)
=3×3×43×(0.7×1.7×3.7)÷(0.7×1.7×3.7)
=3×3×43
=9×43
=(10-1)×43
=430-43
=387