A stationery store sells a kind of electronic dictionary, and each unit can earn a profit of 15 yuan. After the sale (4/5), in order to recover funds as soon as possible, each unit will be sold at a reduced price of 3 yuan. When all are sold out, a total profit will be obtained 864 yuan. How many such electronic dictionaries have been sold in stationery stores?
某文具店出售一种电子辞典，每售出一台可获得利润15元，售出(4/5)后，为了尽快回收资金，每台降价3元出售，当全部售完后，共获利润864元．文具店共卖出这种电子辞典多少台？
<gadget id="calculator">4 / 5</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">(4/5) * 15</gadget>
<output>12</output>

<gadget id="calculator">(4/5) * 3</gadget>
<output>12/5 = around 2.4</output>

<gadget id="calculator">(12/5) - 3 - 12</gadget>
<output>-63/5 = around -12.6</output>

<gadget id="calculator">12 + 15 + (-63/5)</gadget>
<output>72/5 = around 14.4</output>

<gadget id="calculator">864 / (72/5)</gadget>
<output>60</output>

<result>60</result>