After adding 25 liters of gasoline, Uncle Zhang plans to drive to a destination 240 kilometers away. If each liter of gasoline can drive a total of 6.4 kilometers, how many liters of gasoline will he need to add to drive to his destination?
张叔叔加了25升汽油后准备驾车去240千米远的目的地，若每升汽油可共行驶6.4千米，他还需要加多少升汽油才能驶到目的地？
<gadget id="calculator">240 / 6.4</gadget>
<output>37.5</output>

<gadget id="calculator">37.5 - 25</gadget>
<output>12.5</output>

<result>12.5</result>