In a box containing 4 black balls and 2 white balls, what is the probability of drawing a white ball?
在一个装有4个黑球和2个白球的盒子里，摸到白球的可能性是多少．
<gadget id="calculator">4 + 2</gadget>
<output>6</output>

<gadget id="calculator">2 / 6</gadget>
<output>1/3 = around 0.333333</output>

<result>1/3 = around 0.333333</result>