The original price of a certain commodity is 36 yuan. After the price reduction, the sales volume of the day has increased by half, and the income has also increased (1/3). How much is the price reduction for each item?
某种商品每件原价36元，降价后当天销售量增加了一半，收入也增加了(1/3)，每件降价多少元．
<gadget id="calculator">36 * 1.5</gadget>
<output>54</output>

<gadget id="calculator">54 - 48</gadget>
<output>6</output>

<gadget id="calculator">6 / 1.5</gadget>
<output>4</output>

<result>4</result>