When a number is divided by 3, the quotient is 18 and the remainder is 2. What is the number?
一个数除以3，商是18，余数是2，这个数是多少．
<gadget id="calculator">18 * 3</gadget>
<output>54</output>

<gadget id="calculator">54 + 2</gadget>
<output>56</output>

<result>56</result>