<span>b - 13/15 = 13/45 умножим обе части на 45, получим:</span>
<span>45b - 39 = 13</span>
<span>45b = 13 + 39</span>
<span>45b = 52</span>
<span>b = 52/45</span>
<span>b = 1 целая 7/45</span>
76 242 783 195
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