There are more than 20 exercise books in Class 4 and 2; if it is distributed to 2 students on average, there will be one more book; if it is distributed to 3 students on average, there will be one more book; 1 copy. How many are these exercise books?
四2班有二十几本练习本；如果平均分给2个同学，则多出1本；如果平均分给3个同学，也多出1本；如果平均分给4个同学，也多出1本．这些练习本有多少．
<gadget id="calculator">3 * 4</gadget>
<output>12</output>

<gadget id="calculator">12 * 2</gadget>
<output>24</output>

<gadget id="calculator">24 + 1</gadget>
<output>25</output>

<result>25</result>