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①10.64÷2.8+7.54÷0.26②0.2608÷0.16+4÷1.25③39.05÷7.1×4.2+5.58④15-(8-2)⑤4-3+5⑥11+7-9⑦5X+2=7X-8⑧2X+20=4X-24⑨6(X-1)=7(X-3)

题目详情
①10.64÷2.8+7.54÷0.26      ②0.2608÷0.16+4÷1.25        ③39.05÷7.1×4.2+5.58
④15-(8-2) ⑤4-3+5                ⑥11+7-9
⑦5X+2=7X-8           ⑧2X+20=4X-24          ⑨6(X-1)=7(X-3)
▼优质解答
答案和解析
①10.64÷2.8+7.54÷0.26
=3.8+29
=32.8;
②0.2608÷0.16+4÷1.25 
=1.63+3.2
=4.83;
③39.05÷7.1×4.2+5.58
=23.1+5.58
=28.68;
④15-(8-2)
=15-6
=9;
⑤4-3+5
=1+5
=6;
⑥11+7-9
=18-9
=9;
⑦5X+2=7X-8
5x+2-5x=7x-5x-8
         2=2x-8
      2x-8=2
    2x-8+8=2+8
        2x=10
     2x÷2=10÷2
         x=5;
⑧2X+20=4X-24 
2X+20-2x=4X-2x-24
         20=2x-24
      2x-24=20
   2x-24+24=20+24
         2x=44
      2x÷2=44÷2
         x=22;
 ⑨6(X-1)=7(X-3)
   6x-6=7x-21
    6x-6+6=7x-21+6
        6x=7x-15
     6x-6x=7x-6x-15
         0=x-15
      x-15=0
   x-15+15=0+15
         x=15.