It costs 28 yuan to buy 5 pens. According to this calculation, how much more yuan will be needed to buy 8 more pens?
买5支钢笔需要28元，照这样计算，再买8支钢笔，还需要多少元？
<gadget id="calculator">28 / 5</gadget>
<output>28/5 = around 5.6</output>

<gadget id="calculator">(28/5) * 8</gadget>
<output>224/5 = around 44.8</output>

<result>224/5 = around 44.8</result>