Add 5 to a number, multiply by 5, subtract 5, and divide by 5 to get 25. What is this number?
某数加上5，乘以5，减去5，除以5得25．这个数是多少．
<gadget id="calculator">25 * 5</gadget>
<output>125</output>

<gadget id="calculator">125 + 5</gadget>
<output>130</output>

<gadget id="calculator">130 / 5</gadget>
<output>26</output>

<gadget id="calculator">26 - 5</gadget>
<output>21</output>

<result>21</result>