In "Plants vs. Zombies", it takes 10 minutes for the barrel zombie to eat the nut wall alone, and it takes 15 minutes for the barricade zombie to eat the nut wall alone. Now the two zombies are eating together. Because the roadblock zombie was hit by the pea shooter, it took 8 minutes to finish the nut wall. How many minutes did the roadblock zombie eat?
《植物大战僵尸》中，铁桶僵尸单独吃完坚果墙需10分钟，路障僵尸单独吃完坚果墙需15分钟．现在两个僵尸一起吃，由于路障僵尸中途被豌豆射手打中伤亡，结果一共用了8分钟才吃完坚果墙，那么路障僵尸吃了多少分钟？
<gadget id="calculator">1 / 10</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">(1/10) * 8</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">1 - (4/5)</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 / 15</gadget>
<output>1/15 = around 0.066667</output>

<gadget id="calculator">(1/5) / (1/15)</gadget>
<output>3</output>

<result>3</result>