Less than $1 US Dollar
Unless it is a purple bill with a "Miguel Hidalgo" on the front (see related links), it only has numismatic value nowadays.
In fact it is valued for less than 10 dollars, as it is no longer legal tender. It may have some numismatic value, though.
To determine the value of a 1989 "El Banco de México pagará cinco mil pesos a la vista al portador" note worth 5,000 pesos in U.S. dollars, you would need to check the current exchange rate for Mexican pesos to U.S. dollars. As of my last knowledge update, the exchange rate typically fluctuates around 18-20 pesos per dollar, which would give a rough value of around $250 to $277 USD. However, for an accurate and current value, please check the latest exchange rates.
it is a fake coin and has no value
The "face value" of a coin is whatever is inscribed on it, hence the term "face value". The face value of a 10 Pence coin is 10 Pence.
A gold coin with the word Exano inscribed is counterfeit in the world. The coin should be appraised to verify the value. Some coins that are gold or silver are only worth the metal weight.
your piano was made in 1925
rate currencies change all the time. You can find out the exact rate at a bank where they rate it for you.
1968 coins do not have 1990 inscribed on them.
The face value of an Eire 1 penny coin is 1 penny. It was equal to 1/100 of an Irish pound before the euro.
Modern small dollars have the dates inscribed on the edge of the coin, rather than the front or back. They're worth one dollar each.
I don't know I have the same coin and have been looking everywhere for more info.