Wang Bing reads an extracurricular book and has read 22 pages. The ratio of the number of pages he has read to the number of pages he has not read is 2:5. How many pages does this extracurricular book have?
王兵读一本课外书，已经读了22页，己读页数和未读页数的比是2：5．这本课外书一共有多少页？
<gadget id="calculator">2 + 5</gadget>
<output>7</output>

<gadget id="calculator">2 / 7</gadget>
<output>2/7 = around 0.285714</output>

<gadget id="calculator">22 / (2/7)</gadget>
<output>77</output>

<result>77</result>