A bag contains 3 red balls, 2 blue balls, 3 green balls, and 1 white ball, all of which are identical except for their colours. Randomly draw a ball from the bag, what is the probability of touching the blue ball
袋中有3个红球，2个蓝球，3个绿球，l个白球，球除了颜色不同外完全相同．从袋中任意摸出一个，摸到蓝球的可能性是多少
<gadget id="calculator">3 + 2 + 3 + 1</gadget>
<output>9</output>

<gadget id="calculator">2 / 9</gadget>
<output>2/9 = around 0.222222</output>

<result>2/9 = around 0.222222</result>