18% of the cars in the parking lot are blue. If there are 150 cars in the parking lot, how many cars are blue?

27

Explanation:

"Percent" or "%" means "out of 100" or "per 100", Therefore 18% can be written as  

18 /100 .

When dealing with percentage, the word "of" means "times" or "to multiply".

Finally, lets call the number we are looking for "n".

Putting this altogether we can write this equation and solve for  "n "

while keeping the equation balanced:

n  =  18 /100  ×  150

n  =  2700 /100

n  =  27

27 is 18% of 150