Xiaohua finished reading a book in three days, on the first day (3/10), on the second day he read as much as on the first day, how much did he read on the third day?
小华三天看完一本书，第一天看了(3/10)，第二天看的与第一天一样多，第三天看了几分之几？
<gadget id="calculator">3 / 10</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">1 - (3/10) - (3/10)</gadget>
<output>2/5 = around 0.4</output>

<result>2/5 = around 0.4</result>