An unscrupulous vendor set the selling price of a set of suits at 780 yuan. After being checked by the industrial and commercial management department, he lowered the price of each set to 180 yuan. In this way, he can still get a 20% profit for each set sold. If sold at the original sales price, how much profit can be made per set?
某一不法商贩将一套西服的销售价格定为780元，经过工商管理部门核查后，将每一套的定价下降到180元，这样每卖一套仍可获得20%的利润．如果按原销售价卖出，每套可获暴利多少元？
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 + (1/5)</gadget>
<output>6/5 = around 1.2</output>

<gadget id="calculator">180 / (6/5)</gadget>
<output>150</output>

<gadget id="calculator">780 - 150</gadget>
<output>630</output>

<result>630</result>