It costs Lele 6 yuan more to buy 3 pens than to buy 6 ballpoint pens. The unit price of ballpoint pens is 1.6 yuan per pen. How much is the unit price of pens?
乐乐买3支钢笔比买6支圆珠笔要多花6元，圆珠笔的单价是1.6元/支，钢笔的单价是多少元/支？
<gadget id="calculator">1.6 * 6</gadget>
<output>9.6</output>

<gadget id="calculator">9.6 + 6</gadget>
<output>15.6</output>

<gadget id="calculator">15.6 / 3</gadget>
<output>5.2</output>

<result>5.2</result>