Mom went to the supermarket to buy 2kg of candy, of which (2/5) is fruit candy, (1/4) is sandwich candy, and the rest is milk candy. What percentage of all candy is toffee?
妈妈去超市买了2kg糖果，其中(2/5)是水果糖，(1/4)是夹心糖，其余的是奶糖．奶糖占所有糖果的几分之几？
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 - (2/5) - (1/4)</gadget>
<output>7/20 = around 0.35</output>

<result>7/20 = around 0.35</result>