Sak32 wrote:For each customer, a bakery charges p dollars for the first loaf of bread bought by the customer and charges q dollars for each additional loaf of bought by the customer. What is the value of p?

1) A customer who buys 2 loaves is charged 10 percent less per loaf than a customer who buys a single loaf.

2) A customer who buys 6 loaves of bread is charged 10 dollars.

Statement 1:
Since one loaf costs $p and each additional loaf costs $q, the cost per loaf when 2 loaves are purchased = (p+q)/2.
This value is equal to 10% less than p.
In other words, (p+q)/2 is equal to 90% of p:
(p+q)/2 = .9p
p+q = 1.8p
q = .8p.
No way to solve for p.
INSUFFICIENT.

Statement 2:
Since one loaf costs $p and each additional loaf costs $q, the cost for 6 loaves = p + 5q.
Thus:
p + 5q = 10.
No way to solve for p.
INSUFFICIENT.

Statements combined:
Since we have 2 variables and 2 distinct linear equations, we can solve for each variable.
SUFFICIENT.

The correct answer is C.