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神机妙算细又巧.(计算下面各题能简算的要简算)21.28-21.28÷7×30.32×25×12.52.5×4.7-2.5+2.5×6.3(77.4-3.096÷0.4)÷0.037.74×(2.8-1.3)+1.5×2.26.

题目详情
神机妙算细又巧.(计算下面各题能简算的要简算)
21.28-21.28÷7×3         
0.32×25×12.5        
2.5×4.7-2.5+2.5×6.3     
(77.4-3.096÷0.4)÷0.03                
7.74×(2.8-1.3)+1.5×2.26.
▼优质解答
答案和解析
(1)21.28-21.28÷7×3,=21.28-3.04×3,=21.28-9.12,=12.16;(2)0.32×25×12.5,=0.8×0.4×25×12.5,=(0.8×12.5)×(0.4×25),=10×10,=100;(3)2.5×4.7-2.5+2.5×6.3,=2.5×(4.7-1+6.3),=2.5...