Put the yellow ball and the white ball in the lucky draw box. 6 yellow balls have been put in. To design a lottery activity in which the probability of getting a yellow ball is 4%, how many white balls should be put into the box?
在摸奖箱里放入黄球和白球．已经放进去了6个黄球，要设计一个摸到黄球可能性是4%的摸奖活动，要往箱里放进多少个白球？
<gadget id="calculator">4 / 100</gadget>
<output>1/25 = around 0.04</output>

<gadget id="calculator">6 / (1/25)</gadget>
<output>150</output>

<gadget id="calculator">150 - 6</gadget>
<output>144</output>

<result>144</result>