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6x:7=12:5
10-(7-5x)=2x+(5-3x)

解:(1)6x:7=12:5,
         5×6x=7×12,
           30x=84,
       30x÷30=84÷30,
             x=2.8;

(2)10-(7-5x)=2x+(5-3x),
         10-7+5x=2x+5-3x,
            3+5x=5-x,
          3+5x+x=5-x+x,
          3+6x-3=5-3,
           6x÷6=2÷6,
               x=
分析:(1)根据比例的基本性质,把原式转化为5×6x=7×12,再化简,然后根据等式的性质,在方程两边同时除以30求解,
(2)先化简,再根据等式的性质,在方程两边同时加上x,再减去3,最后除以6求解.
点评:本题考查了学生根据等式的性质和比例的基本性质解方程的能力,注意等号对齐.
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科目:小学数学 来源: 题型:解答题

0.02×0.1=5.06x-4.07x=12-7.8=a+0.4a=
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64.32÷16=6x-4.9x=5.1b+11.9b=1.23÷3=
100×0.01=3.4×0.07=3x+4x=0.42÷0.1=
4.3b-2.7b=7÷0.25=5.1x+2.9x=1.75×0.8=
0.3×0.4=5.4+1.4=2.7x+3.6x=16÷1.6=
10x-3.7x=0.98+1.82=2.5x+4.3x=0.05×0.8=
6.05x-4.96x=3.7a+5.2a=3.2÷1.6=3.12÷0.5=
3.5+7.6=5.1a+3.9a=10×0.75=3b-0.7b=
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72.8÷0.8=2.7b+5b=3.5×3=7.6b-4.3b=
32=2.52=4x+5x=3.5t-t=
8a-3a=7b+b=4c-2c=3.5b+2.7b=
0.32÷0.04=0.51×0.2=0.12+3.4=102=

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