The price of a mobile phone was reduced by 30% last year and 20% this year. After the price reduction this year, the price of each mobile phone is 5600 yuan. What is the price difference between the price of this mobile phone before the price reduction last year and the price reduction this year?
一部手机去年降价30%，今年又降价20%，今年降价后每部售价5600元，这种手机去年降价前的价格与今年降价后的价格差是多少．
<gadget id="calculator">30 / 100</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">1 - (3/10)</gadget>
<output>7/10 = around 0.7</output>

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

<gadget id="calculator">1 - (1/5)</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">(7/10) * (4/5)</gadget>
<output>14/25 = around 0.56</output>

<gadget id="calculator">5_600 / (14/25)</gadget>
<output>10_000</output>

<gadget id="calculator">10_000 - 5_600</gadget>
<output>4_400</output>

<result>4_400</result>