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用简便方法运算1.25x0.25x3232x9.1 11.8x43-860x0.09

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用简便方法运算1.25x0.25x3232x9.1 11.8x43-860x0.09
用简便方法运算1.25x0.25x3232x9.1 11.8x43-860x0.09
1.25 × 0.25 × 3232 × 9.1
= 1.25 × 0.25 × 4 × 8 × 101 × 9.1
= (1.25 × 8)× (0.25 × 4)× (100 - 1)× 9.1
= 10 × 1 × 100 × 9.1 - 1 × 9.1
= 10 × 910 - 9.1
= 9100 - 9.1
= 9090.9
11.8 × 43 - 860 × 0.09
= 11.8 × 43 - 43 × 2 × 10 × 0.09
= 11.8 × 43 - 43 × 1.8
= 43 × (11.8 - 1.8)
= 43 × 10
= 430
【俊狼猎英】团队为你解答
再问: 7.24x0.1+0.5x72.4+0.049x724 45.3x3.2+578x0.68+12x9.25 (72x357+357x28)/(51x7x4) 1991+199.1+19.91+1.991 3.2x31.4+34.3x6.4 非常感谢!!!!!!!!!!!!!!!!!!!!
再答: 7.24 × 0.1 + 0.5 × 72.4 + 0.049 × 724 = 7.24 × 0.1 + 0.5 × 10 × 7.24 + 0.049 × 100 × 7.24 = 7.24 × 0.1 + 5 × 7.24 + 4.9 × 7.24 = 7.24 × (0.1 + 5 + 4.9) = 7.24 × 10 = 72.4 45.3 × 3.2 + 578 × 0.68 + 12 × 9.25 = (72 × 357 + 357 × 28)/ (51 × 7 × 4) = (72 + 28)× 357 ÷ 51 ÷ 28 = 100 × 357 ÷ 51 ÷ 28 = 100 × 7 ÷ 28 = 100 × 7 / 28 = 100 × 1 / 4 = 25 1991 + 199.1 + 19.91 + 1.991 = (2000 - 9)+(200 - 0.9)+ (20 - 0.09)+ (2 - 0.009) = 2000 + 200 + 20 + 2 - 9 - 0.9 - 0.09 - 0.009 = 2222 - 9.999 = 2222 - (10 - 0.001) = 2222 - 10 + 0.001 = 2212 + 0.001 = 2212.001 3.2 × 31.4 + 34.3 × 6.4 = 3.2 × 31.4 + 34.3 × 2 × 3.2 = 3.2 × 31.4 + 68.6 × 3.2 = 3.2 × (31.4 + 68.6) = 3.2 × 100 = 320
再问: 45.3 × 3.2 + 578 × 0.68 + 12 × 9.25 谢谢谢谢谢谢谢谢谢谢谢谢!!!
再答: 45.3x3.2+578x0.68+12x9.25 =45.3×3.2+57.8×6.8+12×﹙9+0.25﹚ =﹙57.8-12.5﹚×3.2+57.8×6.8+12×9+12×0.25 =57.8×3.2-12.5×3.2+57.8×6.8+12×﹙10-1﹚+3×﹙4×0.25﹚ =57.8×﹙3.2+6.8﹚-12.5×0.8×4+12×10-12+3×1 =578-4+120-12+3 =﹙578+120+3﹚-﹙4+12﹚ =701-16 =685 还有,上面有一道计错了 1.25 × 0.25 × 3232 × 9.1 = 1.25 × 0.25 × 4 × 8 × 101 × 9.1 = (1.25 × 8)× (0.25 × 4)× (100 + 1) × 9.1 = 10 × 1 × (100 + 1)× 9.1 = 91 × (100 + 1) = 91 × 100 + 91 = 9100 + 91 = 9191