... “In the end, he(Bagman) turned pretty nasty,” said Fred. “Told us we were too young to gamble, and he wasn't giving us anything.”
“So we asked for our money back,” said George glowering.
“He didn't refuse!” gasped Hermione.
“Right in one,” said Fred.
“But that was all your savings!” said Ron.
“Tell me about it,” said George. ...
Harry Potter and the Goblet of Fire
What does "right in one" mean? Is it short for something? Maybe Fred meant Bagman just gave them one Galleon(the money in wizarding world)?