There are 5 red balls, 2 white balls, and 6 yellow balls in the cloth bag. If you touch one of the balls, what is the probability of getting a red ball?
布袋里有5个红球，2个白球，6个黄球，现在从中摸一只，摸到红球的可能性是多少．
<gadget id="calculator">5 + 2 + 6</gadget>
<output>13</output>

<gadget id="calculator">5 / 13</gadget>
<output>5/13 = around 0.384615</output>

<result>5/13 = around 0.384615</result>