A fountain pen is 8.3 yuan, and a ballpoint pen is 2.5 yuan. How much does a pen cost more than a ballpoint pen?
一支钢笔8.3元，一支圆珠笔2.5元．一支钢笔比一支圆珠笔贵几元？
<gadget id="calculator">8.3 - 2.5</gadget>
<output>5.8</output>

<result>5.8</result>