There are six playing cards with their backs up, namely 1, 2, 3 of spades and 1, 2, 3 of hearts. Take any one of them, what is the probability of getting 2 hearts
有六张背面都朝上的扑克牌，分别是黑桃1、2、3和红桃1、2、3．从中任意取一张，取到红桃2的可能性是多少
<gadget id="calculator">1 / 6</gadget>
<output>1/6 = around 0.166667</output>

<result>1/6 = around 0.166667</result>