| 怎样简便就怎样计算: 2.9×1.4+2×0.16 5.4×2.08+66×0.208-2.08 30.8÷[14-(9.85+1.07)] [(12.5+1.25+0.125)×80-999]÷0.03. |
| (1)2.9×1.4+2×0.16 =4.06+0.32, =4.38; (2)5.4×2.08+66×0.208-2.08 =5.4×2.08+6.6×2.08-2.08, =(5.4+6.6-1)×2.08, =11×2.08, =22.88; (3)30.8÷[14-(9.85+1.07)] =30.8÷[14-10.92] =30.8÷3.08, =10; (4)[(12.5+1.25+0.125)×80-999]÷0.03 =[(12.5×80+1.25×80+0.125×80)-999]÷0.03, =[(1000+100+10)-999]÷0.03, =[1110-999]÷0.03, =111÷0.03, =3700. |
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