2. A stationery store that operates both wholesale and retail has the following rule: If you buy 51 pencils or more (including 51), you pay the wholesale price; if you buy 50 pencils or fewer (including 50), you pay the retail price. The wholesale price for 60 pencils is 1 yuan cheaper than the retail price for 60 pencils. Now, the class leader, Xiao Wang, comes to buy pencils. If he buys one pencil for each student, he must pay the retail price, which costs $m$ yuan ($m$ is a positive integer); but if he buys 10 more pencils, he can pay the wholesale price, which also costs exactly $m$ yuan. How many students does Xiao Wang have?
(Tip: Let the whole class have $x$ students, the equation is $\frac{60 m}{x}-\frac{60 m}{x+10}$ $=1(40<x \leqslant 50)$, solving it yields $x=50)$