If a commodity is sold at the original price with a profit of 20% of the cost, and then sold at 90% of the original price, the total profit obtained is 20% higher than the original. How many times will the sales volume after the price reduction be the original sales volume?
某种商品按原定价出售每件利润为成本的20%，后来按原价的90%出售，获得的总利润比原来增加20%，那么降价后的销售量是原销售量的几倍？
<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">100 * (6/5)</gadget>
<output>120</output>

<gadget id="calculator">120 - 100</gadget>
<output>20</output>

<gadget id="calculator">20 * 10</gadget>
<output>200</output>

<gadget id="calculator">200 * (6/5)</gadget>
<output>240</output>

<gadget id="calculator">90 / 100</gadget>
<output>9/10 = around 0.9</output>

<gadget id="calculator">120 * (9/10)</gadget>
<output>108</output>

<gadget id="calculator">108 - 100</gadget>
<output>8</output>

<gadget id="calculator">240 / 8</gadget>
<output>30</output>

<gadget id="calculator">30 / 10</gadget>
<output>3</output>

<result>3</result>