There are 7 yellow balls and 3 red balls of the same size in a bag. Close your eyes and touch any ball from the bag. What is the probability of finding a yellow ball?
袋子里有大小相同的黄球7个，红球3个，闭上眼睛从袋中任意摸一个球，摸出黄球的可能性是多少．
<gadget id="calculator">7 + 3</gadget>
<output>10</output>

<gadget id="calculator">7 / 10</gadget>
<output>7/10 = around 0.7</output>

<result>7/10 = around 0.7</result>