There are 5 red balls, 3 yellow balls, and 2 blue balls in a cardboard box. If you take one ball at random, what is the probability that it is not a blue ball?
纸盒里有5个红球，3个黄球，2个蓝球，任取一次，不是蓝球的可能性是多少．
<gadget id="calculator">5 + 3</gadget>
<output>8</output>

<gadget id="calculator">5 + 3 + 2</gadget>
<output>10</output>

<gadget id="calculator">8 / 10</gadget>
<output>4/5 = around 0.8</output>

<result>4/5 = around 0.8</result>