A×(2.3+1.6)=4.2×2.3+b
a*3,9=9,67+b
дальше не знаю
Ответ 6
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659-(345-х)=427
345-х=657-427
345-х=230
х=345-230
х=115
659-(345-115)=427
427=427
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102.103.104.105.
123.124.125.
120.130.140.150
201.203.204.205
210.230.240.250.
301.302.304.305
310.320.340.350
401.402.403.405.
410.420.430.450.
501.502.503.504
510.520.530.540.
213.214.215.231.234.235.241.243.245.
312.314.315.321.324.325.345
412.413.415.421.423.425.431.432.435.
512.513.514.521.523.524.531.532.534.541.542.543.
Хватит)))