The unit price of a chair in a shopping mall is 60% of the desk, and the chair is 20 yuan cheaper than the desk. Do you know how much the price of this set of desks and chairs is? (solution by equation)
某商场里一把椅子的单价是课桌的60%，椅子比课桌便宜20元，你知道这一套桌椅的售价是多少元吗？(用方程解)
<gadget id="calculator">60 / 100</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">1 - (3/5)</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">20 / (2/5)</gadget>
<output>50</output>

<gadget id="calculator">50 * (3/5)</gadget>
<output>30</output>

<gadget id="calculator">30 + 50</gadget>
<output>80</output>

<result>80</result>