There are 9 pairs of shoes in Aunt Li's shoe cabinet. If any shoe is taken from the shoe cabinet, what is the probability that it is the left foot?
李阿姨的鞋柜中有9双鞋，从鞋柜中任意拿出一只鞋，是左脚的可能性是多少．
<gadget id="calculator">9 + 9</gadget>
<output>18</output>

<gadget id="calculator">9 / 18</gadget>
<output>1/2 = around 0.5</output>

<result>1/2 = around 0.5</result>