Context
US$ 50 is a bill or a small monthly amount; it is appropriate to compare the bid rate If you sell dollars to the bank, they pay you the bid rate; If you buy, you pay the one to sell.
As a historical reference: a week ago (06/11) US$ 50 cost $ 78.500,00 (0,00%); a month ago, $ 76.750,00 (+2,28%); in the latter 30 days the range was of $ 76.500,00 a $ 78.500,00 (daily sales data from ArgentinaDatos.com).
Keep in mind: Buying at the official rate has been open to individuals since 2025, but each bank has its own price and some charge a fee.
The other way around? Passing pesos to official dollar.