The construction team built a road. On the first day I repaired the full length (3/10), and on the second day I repaired more than the first day (1/5). How much is left unrepaired?
工程队修一条公路．第一天修了全长的(3/10)，第二天比第一天多修了(1/5)．还有多少没修？
<gadget id="calculator">3 / 10</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 + (1/5)</gadget>
<output>6/5 = around 1.2</output>

<gadget id="calculator">(6/5) * (3/10)</gadget>
<output>9/25 = around 0.36</output>

<gadget id="calculator">1 - (3/10) - (9/25)</gadget>
<output>17/50 = around 0.34</output>

<result>17/50 = around 0.34</result>