Solve the equation: (3/5)x-(1/2)x-2.4=(2/5).
解方程：(3/5)x-(1/2)x-2.4=(2/5)．
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">2.4 + (2/5)</gadget>
<output>2.8</output>

<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">(3/5) - (1/2)</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">2.8 / (1/10)</gadget>
<output>28</output>

<result>28</result>