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初一的有理数乘法的结合律,交换律,分配律的计算题,附加答案,谢谢各位了!!

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初一的有理数乘法的结合律,交换律,分配律的计算题,附加答案,谢谢各位了!!
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答案和解析
8.75-0.35+(1.25-6.65) =(8.75+1.25)-(0.35+6.65) =10-7 =3 7.2×14.5+17×2.8 =7.2×(17-2.5)+17×2.8 =7.2×17-7.2×2.5+17×2.8 =17×(7.2+2.8)-7.2×2.5 =17×10-7.2×2.5 =170-18 =152 12.8×34.5+12.8×12.3+46.8×87.2 =12.8×(34.5+12.3)+46.8×87.2 =12.8×46.8+46.8×87.2 =46.8×(12.8+87.2) =4680 9.875-(3又八分之七-75%)+3又四分之一 =(9.875-3.875)+(0.75+3.25) =6+4 =10 0.8888×0.6+0.2222×7.6 =0.2222×4×0.6+0.2222×7.6 =0.2222×(2.4+7.6) =0.2222×10 =2.222 56×1.02-1.4×0.8 =5.6×10.2-0.2×5.6=5.6×10 =56 465×8.2+465×29.6-365×37.8 =465×(8.2+29.6)-365×37.8 =465×37.8-365×37.8 =37.8×(465-365) =37.8×100 =3780 4.25×166-42又二分之一×14.2+24×5.75 =4.25×166-42.5×14.2+24×5.75 =4.25×(166-142)+24×5.75 =4.25×24+24×5.75 =24×(4.25+5.75) =24×10 =240