There are 9 red balls and several white balls in a pocket, they are exactly the same except for their color, if any ball is drawn from them, the probability of drawing a red ball is (3/5), then how many white balls are less than the red balls.
口袋中有9个红球和若干个白球，它们除颜色外完全相同，从中任摸出一个球，摸到红球的可能性是(3/5)，则白球比红球少多少个．
<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">9 / (3/5)</gadget>
<output>15</output>

<gadget id="calculator">15 - 9</gadget>
<output>6</output>

<gadget id="calculator">9 - 6</gadget>
<output>3</output>

<result>3</result>