Master Li made a part design drawing with a scale of 10:1. The length of the part measured on the drawing is 30 cm. What is the actual length of the part in centimeters?
李师傅制作一张零件设计图，比例尺为10：1，图纸上测量零件的长为30厘米，这个零件实际长多少厘米．
<gadget id="calculator">10 / 1</gadget>
<output>10</output>

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

<result>3</result>