Percent and problem solving: sales tax
1. the purchase price of a camcorder is $799. what is the total price if the sales tax rate is 7.5% ?

799$ is the 100% price of the camcorder & you want to find out how much would 7.5% of the total price is, then add it to the total price. More explanation on how to do it: 

799$ > 100% 
> 7.5% 
Using cross Multiplication: 
7.5 * 799 = 5992.5 / 100 = 59.925$ 

Now you know that the sales taxes = 59.925$ 
To find the total price of the camcorder (including the taxes), just add the sales taxes to the purchase price: 
799$ + 59.925$ = 858.925$