There are 8 red balls, 3 white balls, and 1 black ball in a box. If a ball is randomly drawn from the box, what is the probability of getting a white ball?
盒子里装有8个红球，3个白球，1个黑球，任意从中摸出一个球，摸到白球的可能性是多少．
<gadget id="calculator">8 + 3 + 1</gadget>
<output>12</output>

<gadget id="calculator">3 / 12</gadget>
<output>1/4 = around 0.25</output>

<result>1/4 = around 0.25</result>