cloth bag contains 10 white ping-pong balls and 15 yellow ping-pong balls of the same size. If one of them is drawn randomly, what is the probability of touching a white ping pong ball?
一个布袋中有大小一样的白色乒乓球10个，黄色乒乓球15个．从中任意摸出一个，摸到白色乒乓球的可能性是多少．
<gadget id="calculator">10 + 15</gadget>
<output>25</output>

<gadget id="calculator">10 / 25</gadget>
<output>2/5 = around 0.4</output>

<result>2/5 = around 0.4</result>