Xiaohua reads a book, read this book on the first day (3/25), read this book on the second day (1/5), and read this book on the third day (1/10) ), how much of this book have you read in these three days?
小华看一本书，第一天看了这本书的(3/25)，第二天看了这本书的(1/5)，第三天看了这本书的(1/10)，这三天一共看了这本书的几分之几？
<gadget id="calculator">3 / 25</gadget>
<output>3/25 = around 0.12</output>

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

<gadget id="calculator">1 / 10</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">(3/25) + (1/5) + (1/10)</gadget>
<output>21/50 = around 0.42</output>

<result>21/50 = around 0.42</result>