A $9 sales tax is charged for a $200 purchase. At this rate what is the sales tax for a $300 purchase

Answer: $13.50 sales tax is charged for $300 because;

Step-by-step explanation:

If you were to do this the easy way you would do,

200 divided by 2 = 100 so;

9 divided by 2 = 4.5

and then since 100 is a ratio in a way they you can do

4.5 times 3 which equals 13.5

:D <3