On a map with a scale of (1/4,000,000), the length of the expressway in A and B is measured to be 3.8 cm. How many kilometers is the actual length of this expressway?
在比例尺是(1/4000000)的地图上，量得A、B两地的高速公路长3.8厘米，这条高速公路实际长多少千米．
<gadget id="calculator">1 / 4_000_000</gadget>
<output>1/4_000_000 = around 0</output>

<gadget id="calculator">3.8 / (1/4_000_000) / 100_000</gadget>
<output>152</output>

<result>152</result>