Mengmeng and her classmates measured the length of the shadow of the flagpole to be 4m on the playground, and at the same time measured the length of the shadow of the upright meter stick to be 40cm. How tall is the school's flagpole?
萌萌和同学们在操场上测量出旗杆影子的长是4m，同时测得直立的米尺影子长是40cm．学校的旗杆有多高？
<gadget id="calculator">40 / 100</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 / (2/5)</gadget>
<output>5/2 = around 2.5</output>

<gadget id="calculator">(5/2) * 4</gadget>
<output>10</output>

<result>10</result>