There are 6 red balls and 3 yellow balls of the same size in the pocket, now draw 1 ball from it, what is the probability of drawing a red ball?
口袋里有同样大小6个红球和3个黄球，现在从中摸出1个球，摸出红球的可能性是多少．
<gadget id="calculator">3 + 6</gadget>
<output>9</output>

<gadget id="calculator">6 / 9</gadget>
<output>2/3 = around 0.666667</output>

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