There are only 5 red balls in a pocket, and a ball is randomly drawn from the pocket, so that the probability of drawing a red ball is (1/3), how many balls of other colors must be put into the pocket.
一个口袋里只有5个红球，从口袋里任意摸出一个球，要使摸出红球的可能性为(1/3)，还要往口袋里放多少个其它颜色的球．
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">5 / (1/3)</gadget>
<output>15</output>

<gadget id="calculator">15 - 5</gadget>
<output>10</output>

<result>10</result>