There are 8 white ping-pong balls and 4 yellow ping-pong balls in the pocket. Now draw 1 ball from it. What is the probability that it is white?
口袋里有8个白色的乒乓球和4个黄色的乒乓球，现在从中摸出1个球，是白色的可能性是多少．
<gadget id="calculator">8 + 4</gadget>
<output>12</output>

<gadget id="calculator">8 / 12</gadget>
<output>2/3 = around 0.666667</output>

<result>2/3 = around 0.666667</result>