There are 25 girls in a class, and 5 boys less than twice the number of girls, how many boys are there?
某班有女生25人，男生比女生的2倍少5人，男生有多少人．
<gadget id="calculator">25 * 2</gadget>
<output>50</output>

<gadget id="calculator">50 - 5</gadget>
<output>45</output>

<result>45</result>