Xiao Ming reads a story book. He reads the whole book (3/5) on the first day, and reads less (2/5) of the whole book on the second day than the first day.
小明看一本故事书，第一天看了全书的(3/5)，第二天比第一天少看了全书的(2/5)，两天共看了多少
<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">(3/5) - (2/5)</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">(1/5) + (3/5)</gadget>
<output>4/5 = around 0.8</output>

<result>4/5 = around 0.8</result>