The ratio of the number of original books between Class A and Class B is 7:4. If Class A gives 65 books to Class B, the ratio of the number of books between Class A and Class B is 2:3. How many books does Class A have?
甲乙两班原有图书本数的比是7：4，如果甲班给乙班65本，则甲、乙两班图书本数的比就是2：3．原来甲班有图书多少本？
<gadget id="calculator">7 + 4</gadget>
<output>11</output>

<gadget id="calculator">7 / 11</gadget>
<output>7/11 = around 0.636364</output>

<gadget id="calculator">2 + 3</gadget>
<output>5</output>

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

<gadget id="calculator">(7/11) - (2/5)</gadget>
<output>13/55 = around 0.236364</output>

<gadget id="calculator">65 / (13/55)</gadget>
<output>275</output>

<gadget id="calculator">275 * (7/11)</gadget>
<output>175</output>

<result>175</result>