There is a batch of bricks, each of which is 60 cm long and 45 cm wide. At least how many of these bricks are needed to form a square?
有一批砖，每块长60厘米，宽45厘米．至少用多少块这样的砖才能铺成一个正方形？
<gadget id="calculator">2 * 2 * 3 * 3 * 5</gadget>
<output>180</output>

<gadget id="calculator">180 / 60</gadget>
<output>3</output>

<gadget id="calculator">180 / 45</gadget>
<output>4</output>

<gadget id="calculator">3 * 4</gadget>
<output>12</output>

<result>12</result>