According to the ratio $$2:3$$, we could know the total is $$5$$. Then the number of boys is $$50\times\frac{2}{5}=20$$. The number of girls is $$50\times\frac{3}{5}=30$$. 
There are $$50$$ students in your class. The ratio of boys to girls is $$2:3$$. How many boys and girls are there? 

A. $$30$$ and $$20$$ 
B. $$20$$ and $$30$$ 
C. $$15$$ and $$20$$ 
D. $$20$$ and $$15$$ 