At the official rate, there were 60,000 of these to the pound when he exchanged it in September; the black market rate was in the millions.
However, it would seem he was ripped off: the notes had already passed their use-by date when he bought them. He's considering going back to complain.
I wonder which is worth least: 1 Zimbabwe dollar, the paper it's printed on, the ink it's printed with, or the metallic strip?