There are more students in the fifth grade than in the fourth grade (3/20), more students in the fourth grade than in the third grade (1/4), and 91 more students in the fifth grade than in the third grade. How many students are there in the third grade?
实验小学的学生，五年级比四年级多(3/20)，四年级比三年级多(1/4)，而五年级学生比三年级多91人，三年级有学生多少人？
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 + (1/4)</gadget>
<output>5/4 = around 1.25</output>

<gadget id="calculator">3 / 20</gadget>
<output>3/20 = around 0.15</output>

<gadget id="calculator">1 + (3/20)</gadget>
<output>23/20 = around 1.15</output>

<gadget id="calculator">(5/4) * (23/20)</gadget>
<output>23/16 = around 1.4375</output>

<gadget id="calculator">(23/16) - 1</gadget>
<output>7/16 = around 0.4375</output>

<gadget id="calculator">91 / (7/16)</gadget>
<output>208</output>

<result>208</result>