15 balls are placed in a box, among which there are 5 red balls, 2 green balls, 7 black balls, and 1 yellow ball. If any ball is drawn from the box, what is the probability of drawing a black ball?
一个盒子里放了15个球，其中有5个红球，2个绿球，7个黑球，1个黄球，从盒子里任意摸一个球，摸出黑球的可能性是多少
<gadget id="calculator">7 / 15</gadget>
<output>7/15 = around 0.466667</output>

<result>7/15 = around 0.466667</result>