In January 2013, a country's first-class mail rates increased to 47 cents for the first ounce, and 25 cents for each additional ounce. If Sabrina spent $19.22 for a total of 54 stamps of these two denominations, how many stamps of each denomination did she buy?

Answer:26 first class stamps and 28 additional.

Step-by-step explanation:

From information given, we can formulate the following equation: 47n + 25 (54-n) = 1922

Now we solve for n.

47 + 1350 + 25n = 1922

47n - 25n = 1922 - 1350

22n=572

n = 26.

Therefore 26 first class stamps and 28 additional. 54 total