Xiaohong buys a pencil case, pays the salesperson 20 yuan, and gets back 14.5 yuan. How much is this pencil case?
小红买一个文具盒，付给营业员20元，找回14.5元，这个文具盒多少元？
<gadget id="calculator">20 - 14.5</gadget>
<output>5.5</output>

<result>5.5</result>