4 pens are 7.6 yuan more expensive than 15 ballpoint pens. The price of each ballpoint pen is 2.8 yuan, how much is each pen?
4支钢笔比15支圆珠笔贵7.6元．每支圆珠笔的价钱是2.8元，每支钢笔多少元？
<gadget id="calculator">15 * 2.8</gadget>
<output>42</output>

<gadget id="calculator">42 + 7.6</gadget>
<output>49.6</output>

<gadget id="calculator">49.6 / 4</gadget>
<output>12.4</output>

<result>12.4</result>