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用简便方法计算.(1)0.34×101(2)7.2×1.25(3)2.94×6.3+3.7×2.94.

题目详情
用简便方法计算.
(1)0.34×101             
(2)7.2×1.25           
(3)2.94×6.3+3.7×2.94.
▼优质解答
答案和解析
(1)0.34×101  
=0.34×(100+1)
=0.34×100+0.34×1
=34+0.34
=34.34
           
(2)7.2×1.25     
=(0.9×8)×1.25
=0.9×(8×1.25)
=0.9×10
=9
      
(3)2.94×6.3+3.7×2.94
=2.94×(6.3+3.7)
=2.94×10
=29.4