Do you know why Jewish people have big noses? Gold.
That does not make sense. Are you an anti-Semite?
It's not based on anything, just a joke.
Grouping people is wrong, but I'd encourage you to learn about how you mocked Jewish people and the suffering they experienced. Falling blame to myths of wealth and silly things happen, so better you read a book or watch a doc.
It's just a joke, you don't have to go off.
But jokes that imply that Jewish people only care about money is bad. It makes them seem greedy and it will make people care less about them and what happens to them.