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用简便方法计算37×20.21.25×3.2×2.520÷0.4÷2.5.

题目详情
用简便方法计算
37×20.2            
1.25×3.2×2.5           20÷0.4÷2.5.
▼优质解答
答案和解析
(1)37×20.2,
=37×(20+0.2),
=37×20+37×0.2,
=740+7.4,
=747.4;

(2)1.25×3.2×2.5,
=1.25×8×0.4×2.5,
=(1.25×8)×(0.4×2.5),
=10×1,
=10;

(3)20÷0.4÷2.5,
=20÷(0.4×2.5),
=20÷1,
=20.