Due to the improved technology of the tape recorder factory, the cost of each unit is reduced (3/20) from the original cost to only 51 yuan. How much is the original cost of each unit?
录音机厂由于改进技术，每台成本比原来降低了(3/20)后每台成本只要51元，原来每台成本多少元？
<gadget id="calculator">3 / 20</gadget>
<output>3/20 = around 0.15</output>

<gadget id="calculator">1 - (3/20)</gadget>
<output>17/20 = around 0.85</output>

<gadget id="calculator">51 / (17/20)</gadget>
<output>60</output>

<result>60</result>