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练习十1.乘法结合律 乘法交换律和结合律 乘法分配律2.√ x √x3.=18x（200+1） =18x200+18 =3600+18 =3618 =125x8+125x20=1000+2500=3500 =15x2x27=30x27=810 =76x（100-1）=76x100-76=7600-76=7524=27x（38+62）=27x100 =2700=84x（99+1）=84x100 =84004.=45x（20-2）=45x20-45x2=900-90=810 =71x（100+1）=71x100+71=7100+71=7171=29x（4x5）=29x20 =580 =25x4x9=100x9=900 =35x（10+2）=35x10+35x2=350+70=420 =6x5x17=30x17=5105.(1)480 480 相等 (2)5544 5544 相等6.=7x（256-  | 