There are 8 red balls and 2 yellow balls in a box, what is the probability of touching the yellow ball?
盒子里有8个红球，2个黄球，摸到黄球的可能性是多少．
<gadget id="calculator">8 + 2</gadget>
<output>10</output>

<gadget id="calculator">2 / 10</gadget>
<output>1/5 = around 0.2</output>

<result>1/5 = around 0.2</result>