Dad intends to pave the upper bricks for the bright little study room. It takes 90 square bricks with a side length of 2 decimeters. If the square bricks with a side length of 3 decimeters are used instead, how many square bricks are needed? (Solve with ratio)
爸爸打算给亮亮的小书房铺上方砖，用边长2分米的方砖需要90块，如果改用边长3分米的方砖，需要方砖多少块？(用比例解)
<gadget id="calculator">2 * 2 * 90</gadget>
<output>360</output>

<gadget id="calculator">3 * 3</gadget>
<output>9</output>

<gadget id="calculator">360 / 9</gadget>
<output>40</output>

<result>40</result>