A sealed opaque bag contains 1 red ball, 1 yellow ball and 1 green ball. Xiaohua reaches out and grabs a ball at random. What is the chance of catching the red ball?
一个密封的不透明的袋子装了1只红球、1只黄球和1只绿球，小华伸手任意抓一只球，抓到红球的机会是多少
<gadget id="calculator">1 + 1 + 1</gadget>
<output>3</output>

<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

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