Ok, we need find the price of each dvd unit, then for this we are going to take the total price of the dvd's and divide it by the quantity that was compared.
So we have this:
Total dvd price: 76.57
Number of dvd: 13
Dividing we get:
76.57/13=5.89
The long division is:
76/13 equals 5 and we have a remainder of 11 that goes down, we went down on the 5th of ten, 115 divided by 13 equals 8 and there are 11 remainders left, we lower the 7 of the hundredths, and 117 divided 13 equals 9.
So finally we get that the unitary price of dvd is $5.89.