How many meters are left after 30% of the 3-meter steel wire is cut off?
3米长的钢丝截去30%后，还剩多少米．
<gadget id="calculator">30 / 100</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">3 * (3/10)</gadget>
<output>9/10 = around 0.9</output>

<gadget id="calculator">3 - (9/10)</gadget>
<output>21/10 = around 2.1</output>

<result>21/10 = around 2.1</result>