The perimeter of a triangle is (7/10) decimeters, and the lengths of two sides are (1/5) decimeters and (3/10) decimeters respectively. What is the length of the other side?
一个三角形的周长是(7/10)分米，其中两条边的长分别是(1/5)分米、(3/10)分米，另一条边的长是多少分米？
<gadget id="calculator">7 / 10</gadget>
<output>7/10 = around 0.7</output>

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

<gadget id="calculator">3 / 10</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">(7/10) - (1/5) - (3/10)</gadget>
<output>1/5 = around 0.2</output>

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