A wire is 600m long, and (3/4) is used up, how many meters are used up.
一根电线长600m，用去了(3/4)，用去了多少米．
<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">600 * (3/4)</gadget>
<output>450</output>

<result>450</result>