For a bundle of wires, 0.15 kilometers are used first, and then 0.25 kilometers are used, and the used one is 0.3 kilometers more than the rest. How many kilometers are left in this bundle of wires?
一捆电线，先用去0.15千米，又用去0.25千米，用去的比剩下的多0.3千米．这捆电线还剩多少千米？
<gadget id="calculator">0.25 - 0.3</gadget>
<output>-0.05</output>

<gadget id="calculator">0.15 + (-0.05)</gadget>
<output>0.1</output>

<result>0.1</result>