There are 680 students in a certain elementary school this year, an increase of 40 compared to last year. What percentage is the increase this year compared to last year?
某小学今年有680名学生，比去年增加了40名，今年比去年增加了百分之几？
<gadget id="calculator">680 - 40</gadget>
<output>640</output>

<gadget id="calculator">40 / 640</gadget>
<output>1/16 = around 0.0625</output>

<result>1/16 = around 0.0625</result>