$$2021\div (21+22)=47$$. 
Rick and Roy each stands at different ends of a straight road that is $$2021$$m long. They run toward each other. Rick\textquotesingle s speed is $$21\text{m/s}$$ and Roy\textquotesingle s speed is $$22\text{m/s}$$. They will meet in~\uline{~~~~~~~~~~}~seconds. ($$2016$$ Math League.com contest problem, $$5$$th Grade, Question \#$$26$$) 

(1) $$35$$ 
(2) $$4$$ 
(3) $$47$$ 
(4) $$50$$ 