If you walk 2 kilometers in 20 minutes, how many kilometers will you walk in 40 minutes?
走2千米20分钟，走40分钟走多少千米．
<gadget id="calculator">2 / 20</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">(1/10) * 40</gadget>
<output>4</output>

<result>4</result>