The scale on a drawing of a precision part is 8:1. The length of the part measured on the drawing is 4 cm. What is the actual length of the part?
一种精密零件图纸上的比例尺是8：1，在图上量得零件的长是4厘米，这个零件的实际长度是多少．
<gadget id="calculator">8 / 1</gadget>
<output>8</output>

<gadget id="calculator">4 / 8</gadget>
<output>1/2 = around 0.5</output>

<result>1/2 = around 0.5</result>