Below is an instruction that describes a task. Write a response that appropriately completes the request in English. Please answer in English.

### Instruction:
Reggie is playing marbles with his friend. His friend arrives with 100 marbles. Each game, they bet ten marbles and whoever wins gets to keep all the marbles. After 9 games, Reggie has 90 marbles. How many games has he lost?

### Response:
Since Reggie has 90 marbles, then Reggie and his friend have played 100 - 90 = <<100-90=10>>10 games.
Since the bet is 10 marbles, then Reggie has lost 10 - 9 = <<10-9=1>>1 game.
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