It is known that there are 40 students in Class A of a certain grade, and there are 25 boys in Class A and Class B. How many more girls in Class A than boys in Class B?
已知某年级A班有40人，A班和B班共有男生25人，那么A班的女生比B班的男生多多少人．
<gadget id="calculator">40 - 25</gadget>
<output>15</output>

<result>15</result>