What is 60% of $90?
The whole is 90.
The percent is 60%.
Let n represent the part.
Write a proportion and find the cross products to solve for n.

= 


100n 
= 
60 × 90 

100n 
= 
5,400 

100n ÷ 100 
= 
5,400 ÷ 100 

n 
= 
54 
You could also find the answer by writing and solving an equation:
part 
= 
percentage of whole 

n 
= 
60% × 90 

n 
= 
0.60 × 90 

n 
= 
54 