There are 4 red balls and some white balls in the pocket. Only one ball is touched each time. After touching 30 times, a total of 10 red balls are touched. What is the approximate number of white balls in the pocket?
口袋里有4个红球和一些白球，每次只摸一个球，摸了30次，共摸到10次红球，袋里白球的个数大概多少个
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">4 / (1/3)</gadget>
<output>12</output>

<gadget id="calculator">12 - 4</gadget>
<output>8</output>

<result>8</result>