sidewalk is 90 meters long and 4 meters wide, and the sidewalk is paved with floor tiles with an area of 9 square decimeters. How many such bricks are needed?
一条人行道长90米，宽4米，用面积是9平方分米的地砖铺人行道，需要多少块这样的砖？
<gadget id="calculator">90 * 10</gadget>
<output>900</output>

<gadget id="calculator">4 * 10</gadget>
<output>40</output>

<gadget id="calculator">40 / 9</gadget>
<output>40/9 = around 4.444444</output>

<gadget id="calculator">900 * (40/9)</gadget>
<output>4_000</output>

<result>4_000</result>