The meaning of an English joke (Chinese version)

It turned out to be 3 pence, which can save 6 pence a day.

But if it shows 2 pence, you can save 4 pence for a round trip every day.

So it's 2 pence less (2 pence less than before)

Something like this.

But this is a cold joke.

It's not funny ~

Are you saying that this man is stingy?

I don't understand ~

Hmm. How interesting