fountain pen is 7.3 yuan, which is 2.6 yuan more expensive than a watercolor pen. How much does it cost to buy a fountain pen and a watercolor pen?
一支钢笔7.3元，比水彩笔贵2.6元，买一支钢笔和一支水彩笔一共要多少元？
<gadget id="calculator">7.3 - 2.6</gadget>
<output>4.7</output>

<gadget id="calculator">4.7 + 7.3</gadget>
<output>12</output>

<result>12</result>