When a number is divided by 29, the quotient is 18 and the remainder is 20. What is the number?
一个数除以29，商是18，余数是20，这个数是多少．
<gadget id="calculator">29 * 18</gadget>
<output>522</output>

<gadget id="calculator">522 + 20</gadget>
<output>542</output>

<result>542</result>