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用简便方法计算.(1)27.3+73.2+72.7(2)585+189+215(3)5.85-1.75-0.25(4)768-274-126(5)5.85+1.89+2.15(6)24.8+14.6+15.4(7)42.5-22.17-7.83(8)3.8+1.37+6.2+12.63.

题目详情
用简便方法计算.
(1)27.3+73.2+72.7         
(2)585+189+215
(3)5.85-1.75-0.25         
(4)768-274-126    
(5)5.85+1.89+2.15   
(6)24.8+14.6+15.4
(7)42.5-22.17-7.83   
(8)3.8+1.37+6.2+12.63.
▼优质解答
答案和解析
(1)27.3+73.2+72.7     
=27.3+72.7+73.2
=100+73.2
=173.2

(2)585+189+215
=585+215+189
=800+189
=989

(3)5.85-1.75-0.25       
=5.85-(1.75+0.25)
=5.85-2
=3.85

(4)768-274-126    
=768-(274+126)
=768-400
=368

(5)5.85+1.89+2.15  
=5.85+2.15+1.89
=8+1.89
=9.89

(6)24.8+14.6+15.4
=24.8+(14.6+15.4)
=24.8+30
=54.8

(7)42.5-22.17-7.83   
=42.5-(22.17+7.83)
=42.5-30
=12.5

(8)3.8+1.37+6.2+12.63
=(3.8+6.2)+(1.37+12.63)
=10+14
=24