A class in the sixth grade held a graduates’ sorority meeting, and the class leader went to buy candy. The money he brought happened to be able to buy only 20 kilograms of chocolate candy, or only 30 kilograms of toffee. Teacher Wang did some calculations and decided to buy 8 kilograms of chocolate candy first, and the rest to buy toffee. How many kilograms of toffee can I buy?
六年级某班举行毕业生联谊会，班长去购买糖果，他带的钱正好只能买20千克巧克力糖，或者只能买30千克奶糖．王老师算了一下决定先买8千克巧克力糖，余下的买奶糖，还能买多少千克奶糖？
<gadget id="calculator">1 / 20</gadget>
<output>1/20 = around 0.05</output>

<gadget id="calculator">(1/20) * 8</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 - (2/5)</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">1 / 30</gadget>
<output>1/30 = around 0.033333</output>

<gadget id="calculator">(3/5) / (1/30)</gadget>
<output>18</output>

<result>18</result>