The original price of a commodity is 60 yuan, and it will be sold at a reduced price this month for promotion. After the price cut, the daily sales volume increased by 50% compared with before, so the total sales increased by 20%. How much is the price of this product reduced?
一种商品原定价60元，为促销本月降价出售．降价后每天销售量比以前增加了50%，这样总销售额增加了20%．这种商品降价了多少元．
<gadget id="calculator">50 / 100</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">60 * (1/2)</gadget>
<output>30</output>

<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">60 * (1/5)</gadget>
<output>12</output>

<gadget id="calculator">30 - 60 - 12</gadget>
<output>-42</output>

<gadget id="calculator">60 + (-42)</gadget>
<output>18</output>

<gadget id="calculator">1 + (1/2)</gadget>
<output>3/2 = around 1.5</output>

<gadget id="calculator">18 / (3/2)</gadget>
<output>12</output>

<result>12</result>