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脱式计算,能简算的要简算.12.5×32×2.56.8×9.924.6×4.6+246×0.44+24.66.28÷0.8÷54.85÷0.25+1.25÷0.25.

题目详情
脱式计算,能简算的要简算.
12.5×32×2.5           
6.8×9.9         
24.6×4.6+246×0.44+24.6
6.28÷0.8÷5            
4.85÷0.25+1.25÷0.25.
▼优质解答
答案和解析
(1)12.5×32×2.5  
=12.5×4×8×2.5
=(12.5×4)×(8×2.5)
=50×20
=1000;

(2)6.8×9.9   
=6.8×(10-0.1)
=6.8×10-6.8×0.1
=68-0.68
=67.32;
      
(3)24.6×4.6+246×0.44+24.6
=24.6×4.6+24.6×4.4+24.6×1
=24.6×(4.6+4.4+1)
=24.6×10
=246;

(4)6.28÷0.8÷5 
=6.28÷(0.8×5)
=6.28÷4
=1.57;
          
(5)4.85÷0.25+1.25÷0.25
=(4.85+1.25)÷0.25
=6÷0.25
=24.