There are 6 red balls and 9 white balls in a box, if a ball is randomly drawn from the box, what is the probability of drawing a red ball
一个盒子里有6个红球，9个白球，从盒子里任意摸出一个球，摸到红球的可能性是多少
<gadget id="calculator">6 + 9</gadget>
<output>15</output>

<gadget id="calculator">6 / 15</gadget>
<output>2/5 = around 0.4</output>

<result>2/5 = around 0.4</result>