There are 2 red balls, 1 white ball and 1 yellow ball in a bag, and Xiao Ming only touches one ball at a time, so what is the probability of drawing a white ball
一个袋里有2个红球，白球、黄球各1个，小明每次只摸一个球，那么，摸出白球的可能性是多少
<gadget id="calculator">1 + 1 + 2</gadget>
<output>4</output>

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

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