If the scale of the school plan is 1:1000, the length of the playground measured on the map is 30cm, what is the actual length of the playground in centimeters?
如果学校平面图的比例尺是1：1000，在图上量得操场长是30cm，操场的实际长是多少厘米．
<gadget id="calculator">1 / 1_000</gadget>
<output>1/1_000 = around 0.001</output>

<gadget id="calculator">30 / (1/1_000)</gadget>
<output>30_000</output>

<result>30_000</result>