Department stores are running promotions, 20% off for purchases over 5,000 yuan. Teacher Zhang wants to buy a set of stereos for 5,600 yuan, and Teacher Wang wants to buy a tape recorder for 800 yuan. Now they plan to buy them together. How much can they save compared to buying them separately?
百货商场搞促销，满5000元打八折．张老师要买一套音响5600元，王老师要买一台录音机800元、现在他们打算合起来买，这样比单独买可节省多少元？
<gadget id="calculator">80 / 100</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">1 - (4/5)</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">800 * (1/5)</gadget>
<output>160</output>

<result>160</result>