（2014•上海模拟）计算题91.5+88.8+90.2+270.4+89.6+186.7+91.8；5795.5795÷5.795×579.5；3.75×4.23×36-125×0.423×2.8．

Question

（2014•上海模拟）计算题
91.5+88.8+90.2+270.4+89.6+186.7+91.8；
5795.5795÷5.795×579.5；
3.75×4.23×36-125×0.423×2.8．

Answer 1

（1）91.5+88.8+90.2+270.4+89.6+186.7+91.8
=90+1.5+90-1.2+90+0.2+270+0.4+90-0.4+180+6.7+90+1.8
=90×（1+1+1+3+1+2+1）+（1.5-1.2+0.2+0.4-0.4+6.7+1.8）
=900+9
=909

（2）5795.5795÷5.795×579.5
=5795.5795÷5.795×5.795×100
=5795.5795×100
=579557.95

（3）3.75×4.23×36-125×0.423×2.8
=3.75×4.23×36-12.5×4.23×2.8
=4.23×（3.75×36-12.5×2.8）
=4.23×（12.5×0.3×36-12.5×2.8）
=4.23×12.5×（0.3×36-2.8）
=4.23×12.5×（10.8-2.8）
=4.23×12.5×8
=423