It costs 18 yuan to buy a pair of trousers, and the price of a jacket is twice that of a pair of trousers. How much does it cost to buy such a set of clothes?
买一条裤子需18元钱，一件上衣的价钱是一条裤子的2倍．买这样一套衣服需要多少元钱？
<gadget id="calculator">18 * 2</gadget>
<output>36</output>

<gadget id="calculator">36 + 18</gadget>
<output>54</output>

<result>54</result>