用简便方法计算．①69.6÷3.2÷2.5②4.8×0.27+0.52×2.7③7.59×102④32.6×1.01-0.1×3.26⑤0.25×0.89×4⑥4.5×98⑦4.8÷2.5÷4⑧12.5×1.36×0.8⑨8.8×1.25

Question

用简便方法计算．

①69.6÷3.2÷2.5	②4.8×0.27+0.52×2.7	③7.59×102
④32.6×1.01-0.1×3.26	⑤0.25×0.89×4	⑥4.5×98
⑦4.8÷2.5÷4	⑧12.5×1.36×0.8	⑨8.8×1.25

Answer 1

①69.6÷3.2÷2.5
=21.75÷2.5
=8.7

②4.8×0.27+0.52×2.7
=（4.8+5.2）×0.27
=10×0.27
=2.7

③7.59×102
=7.59×（100+2）
=7.59×100+7.59×2
=759+15.18
=774.18

④32.6×1.01-0.1×3.26
=（1.01-0.01）×32.6
=1×32.6
=32.6

⑤0.25×0.89×4
=（0.25×4）×0.89
=1×0.89
=0.89

⑥4.5×98
=4.5×（100-2）
=4.5×100-4.5×2
=450-9
=441

⑦4.8÷2.5÷4
=4.8÷（2.5×4）
=4.8÷10
=0.48

⑧12.5×1.36×0.8
=（12.5×0.8）×1.36
=10×1.36
=13.6

⑨8.8×1.25
=1.1×8×1.25
=1.1×（8×1.25）
=1.1×10
=11