There are 3 red balls, 2 yellow balls and 1 white ball in a box. The balls are identical except for their color. If one is randomly drawn from the box, what is the probability of finding a red ball?
盒子里有3个红球、2个黄球和1个白球，球除颜色外完全相同，从里面随便摸出一个，摸出红球的可能性是多少．
<gadget id="calculator">3 + 2 + 1</gadget>
<output>6</output>

<gadget id="calculator">3 / 6</gadget>
<output>1/2 = around 0.5</output>

<result>1/2 = around 0.5</result>