The scale of a drawing of a part is 10:1, and the measured length on the drawing is 30 centimeters, so what is the actual length in centimeters?
一种零件制作图的比例尺10：1，量的图上长度是30厘米，那么实际长度是多少厘米．
<gadget id="calculator">10 / 1</gadget>
<output>10</output>

<gadget id="calculator">30 / 10</gadget>
<output>3</output>

<result>3</result>