The customer paid $15.95 for the first compact disc and $3.99 for the other 5. Together he or she spent S = 5(3.99) + 15.95 on 6 compact discs.
All answer choices look very similar and consist of two parts: 5x (x is close to 3.99) and y (y is close to 15.95). Now, let's compare each part separately, marking it:
A) 5(4.00) + 15.90 --> greater + less. It could be a right answer
B) 5(4.00) + 15.95 --> greater + equal --> greater than S. It can't be a right answer.
C) 5(4.00) + 16.00 --> greater + greater --> greater than S. It can't be a right answer.
D) 5(4.00 - 0.01) + 15.90 --> equal + less --> less than S. It can't be a right answer.
E) 5(4.00 - 0.05) + 15.95 --> less + equal --> less than S. It can't be a right answer.
So, only A can be correct. We can check it with calculations: 5(4.00) + 15.90 = 5(3.99 + 0.01) + 15.90 = 5(3.99) + 0.05 + 15.90 = 5(3.99) + 15.95.