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?
Let's think step by step below.
1
Reggie has lost 10 marbles because 100 - 90 = 10.

Since each game was worth 10 marbles, Reggie has lost 1 game.

.

The answer: 1