A sidewalk is 90 meters long and 6 meters wide. How many square floor tiles with an area of 4 square meters are needed to pave the sidewalk?
一条人行道长90米，宽6米．用面积是4平方米的正方形地砖铺人行道，需要多少块？
<gadget id="calculator">6 / 4</gadget>
<output>3/2 = around 1.5</output>

<gadget id="calculator">90 * (3/2)</gadget>
<output>135</output>

<result>135</result>