A box contains 24 small balls of the same size in three different colors, red, yellow, and blue. It is known that each time a small ball is taken out, the probability of red is (1/4), which is 2 of the probability of yellow. times, how many blue balls are in the box.
一个盒子中装有红、黄、蓝三种不同颜色的大小相同的小球24个，已知每次拿出一个小球，红色的可能性是(1/4)，是黄色可能性的2倍，盒子中蓝色小球有多少．
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">24 * (1/4)</gadget>
<output>6</output>

<gadget id="calculator">6 / 2</gadget>
<output>3</output>

<gadget id="calculator">24 - 6 - 3</gadget>
<output>15</output>

<result>15</result>