A classroom is 8.4 meters long and 7.2 meters wide. If square bricks with a side length of 0.6 meters are used to pave the floor, at least how many square bricks are needed?
一间教室长8.4米，宽7.2米，如果用边长0.6米的方砖铺地，至少要多少块方砖？
<gadget id="calculator">0.6 * 0.6</gadget>
<output>0.36</output>

<gadget id="calculator">7.2 / 0.36</gadget>
<output>20</output>

<gadget id="calculator">8.4 * 20</gadget>
<output>168</output>

<result>168</result>