When a number is divided by 8, the quotient is 72 and the remainder is 4. What is the number?
一个数除以8，商是72，余数是4，这个数是多少．
<gadget id="calculator">72 * 8</gadget>
<output>576</output>

<gadget id="calculator">576 + 4</gadget>
<output>580</output>

<result>580</result>