When Li Lei reads a book, he reads more pages on the first day than on the second day (1/3), and the number of pages he reads on the second day is equivalent to (1/7) the number of pages in the whole book, and the number of pages he reads on the first day What fraction of the number of pages in the book?
李磊读一本书，第一天读的页数比第二天多(1/3)，第二天读的页数相当于全书页数的(1/7)，第一天读的页数相当于全书页数的几分之几？
<gadget id="calculator">1 / 7</gadget>
<output>1/7 = around 0.142857</output>

<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">1 + (1/3)</gadget>
<output>4/3 = around 1.333333</output>

<gadget id="calculator">(1/7) * (4/3)</gadget>
<output>4/21 = around 0.190476</output>

<result>4/21 = around 0.190476</result>