Sally made $0.75 * 20=15$ shots originally. Letting $x$ be the number of shots she made, we have $\frac{15+x}{30}=0.6$. Solving for $x$ gives us $x=3$ 
After Sally takes 20 shots, she has made $75 \textbackslash\%$ of her shots. After she takes 10 more shots, she drops her percentage to $60 \textbackslash\%$. How many of the last 5 shots did she make? (adapted from 2004 AMC 8, Question\#6) 

a. $$2$$ 
b. $$3$$ 
c. $$4$$ 
d. $$5$$ 
e. $$6$$ 