SILVER: 10, 15, and 20 dingos
COPPER: 1, 2, and 3 dingos.
The ACMs (automatic change machines) accept silver coins and return change as follows:
After Dingus converted into copper the 145d he had in silver coins, his friend W.G.Ringus counted them and successfully reconstructed the original composition of silver coins, previously unknown to him.
It is up to you to find both the input and the output
- if the Wise Guy did it – you can do it, too.
It is D4, if solved analytically.