7142.85÷3.7÷2.7×1.7×0.7的巧算问题 一定要有过程具体!

法一：把7142.85分解质因数即得7142.85=3*3*3*5*11*13*37*0.01=5*11*13*27*37*0.01
7142.85÷3.7÷2.7×1.7×0.7
=5*11*13*27*37*0.01÷3.7÷2.7×1.7×0.7
=5*11*13*27*37÷37÷27×1.7×0.7
=5*11*13*1.7*0.7
=850.85
法二：7142.85÷3.7÷2.7×1.7×0.7.
=7142.85÷37÷27×17×7
=7142.85×7÷999×17
=49999.95÷999×17
=50.05×17
=850.85

7142.85÷3.7÷2.7×1.7×0.7
=714285/100÷37/100÷27/100×17/100×7/100
=(714285×17×7)/(100×37×27)
=(143×17×7)/20
=17017/20
=850.85

7142.85÷3.7÷2.7×1.7×0.7
=715×3.7×2.7÷3.7÷2.7×1.7×0.7
=715×(3.7÷3.7)×(2.7÷2.7)×(1.7×0.7)
=(715×1)×(1×1.9)
=715×1.19
=850.85