The USA acquired ceded lands by Mexico on Ground Hogs Day,
1848 in the Treaty of Guadelupe Hidalgo.
The USA paid Mexico $15M for 338,6 Million acres for these ceded lands. (4.4 cents per acre)
The USA paid France $15M for 530 Million acres in the Louisiana Purchase (2.8 cents per acre)
The USA gave back current day Mexico lands as part of the Treaty of Guadelupe Hidalgo agreement.
The USA paid the same amount of money to Mexico for 191,400,000 less acres
than they bought from France for the same price. (45years later)