What is the result of -30*((1/2)-(2/3)+0.4).
-30*((1/2)-(2/3)+0.4)的结果为多少．
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">2 / 3</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">(1/2) - (2/3)</gadget>
<output>-1/6 = around -0.166667</output>

<gadget id="calculator">(-1/6) + 0.4</gadget>
<output>0.233333</output>

<gadget id="calculator">30 * 0.233333</gadget>
<output>6.99999</output>

<result>6.99999</result>