There are three colored balls in a box, red, white, and yellow. What is the probability of touching a white ball?
盒子里装有红、白、黄3种颜色球各1个，摸到白球的可能性是多少．
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

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