It took (1/2) days to build a canal of (2/5) kilometers long and (1/4) to repair it. How many miles per day on average?
修一条长(2/5)千米的水渠，当修了它的(1/4)时，用了(1/2)天．平均每天修多少千米？
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

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

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

<gadget id="calculator">(2/5) * (1/2)</gadget>
<output>1/5 = around 0.2</output>

<result>1/5 = around 0.2</result>