2 red balls and 3 white balls are touched 20 times, what is the possible number of touches of red balls?
2个红球3个白球，摸20次，摸到红球的次数可能是多少．
<gadget id="calculator">2 + 3</gadget>
<output>5</output>

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

<gadget id="calculator">20 * (2/5)</gadget>
<output>8</output>

<result>8</result>