When a number is divided by 8, the quotient is 21. What is the number when the remainder is the largest.
一个数除以8，商是21，当余数最大时，这个数是多少．
<gadget id="calculator">8 * 21</gadget>
<output>168</output>

<gadget id="calculator">8 - 1</gadget>
<output>7</output>

<gadget id="calculator">168 + 7</gadget>
<output>175</output>

<result>175</result>