A total of 960 boys stood in a three-story hollow square. Ask: How many people are there on each side of the middle floor?
共有960名男生站成一个三层的空心方阵，问：中间一层每边有多少人？
<gadget id="calculator">960 / 4 / 3</gadget>
<output>80</output>

<gadget id="calculator">80 + 3</gadget>
<output>83</output>

<gadget id="calculator">83 - 2</gadget>
<output>81</output>

<result>81</result>