please help me with my math

Question

 Judy bought 4 CDs at the music store. Each cost $14.95. She was charged 5% sales tax on her purchase. What is the sales tax?

What was the total cost of Judy's purchase?

Answer 1

if she brought 4CDs for 14.95 each then to find the total value for her purchase we must add the cost of each CD together and since each CD had the same price we will multiply 14.95 times 4 which is 59.80 and to find a 5% sales tax that would be that 5$ of the cost is being added to the total cost of the purchase and this is quire similar to exponential growth without the exponent which would be 59.80(0.05) where 0.05 is f hundreths or 5/100 or 5% where you will get 59.80(0.05)=2.99 so the 5% sales tax is $2.99 so if you add 59.80+2.99=62.79 so the total cost of her purchase including sales tax is $62.79