If the number of girls in a class increases (1/4), the number of boys remains the same, and the total number of students is 72. If the number of boys decreases (1/4) and the number of girls remains the same, the total number is 56. How many students are there in this class?
某班若女生增加(1/4)，男生不变，总人数就是72人．若男生减少(1/4)，女生人数不变，总人数就是56人，这个班共有学生多少人．
<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">72 * (1/4)</gadget>
<output>18</output>

<gadget id="calculator">56 - 72</gadget>
<output>-16</output>

<gadget id="calculator">18 + (-16)</gadget>
<output>2</output>

<gadget id="calculator">(1/4) * (1/4)</gadget>
<output>1/16 = around 0.0625</output>

<gadget id="calculator">1 - 1 - (1/4)</gadget>
<output>-1/4 = around -0.25</output>

<gadget id="calculator">(1/4) + (1/16) + (-1/4)</gadget>
<output>1/16 = around 0.0625</output>

<gadget id="calculator">2 / (1/16)</gadget>
<output>32</output>

<gadget id="calculator">(5/4) * 32</gadget>
<output>40</output>

<gadget id="calculator">72 - 40</gadget>
<output>32</output>

<gadget id="calculator">32 + 32</gadget>
<output>64</output>

<result>64</result>