A color bar is 12 meters long, cut off (1/3), and then connect 13 meters, how many meters is the color bar at this time?
一根彩条长12米，截去(1/3)，再接上13米，这时彩条长多少米．
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">1 - (1/3)</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">12 * (2/3)</gadget>
<output>8</output>

<gadget id="calculator">8 + 13</gadget>
<output>21</output>

<result>21</result>