Atlanta Braves First-Place Eliminiation Scenario
Atlanta must win 18 more games (57 total) to avoid elimination from first place.
Here are the final standings in a scenario in which Atlanta finishes in first place with 57 wins:

Team             W	L	PCT	GB
Atlanta          57	105	0.352	0.00
Miami            57	105	0.352	0.00
Washington       56	106	0.346	1.00
New York         56	106	0.346	1.00
Philadelphia     56	106	0.346	1.00

Tie breakers
Atlanta wins the series with Miami 8 games to 5

To construct the scenario, we start with the current standings in the division:
Team             W	L	GL	PCT	GB
Philadelphia     51	37	74	0.580	0.0
New York         51	38	73	0.573	0.5
Miami            39	47	76	0.453	11.0
Atlanta          39	48	75	0.448	11.5
Washington       37	51	74	0.420	14.0

Next, we show how the remaining series of games plays out in the scenario:

Atlanta currently has 2 win(s) against Miami and 3 loss(es).
Atlanta wins 6 additional game(s) against Miami and loses 2.
Atlanta wins the series 8 games to 5.
Atlanta wins 0 additional game(s) against teams outside the division and loses 50.

Atlanta currently has 5 win(s) against New York and 2 loss(es).
Atlanta wins 6 additional game(s) against New York and loses 0.
Atlanta wins the series 11 games to 2.
Atlanta wins 0 additional game(s) against teams outside the division and loses 50.

Atlanta currently has 4 win(s) against Philadelphia and 5 loss(es).
Atlanta wins 4 additional game(s) against Philadelphia and loses 0.
Atlanta wins the series 8 games to 5.
Atlanta wins 0 additional game(s) against teams outside the division and loses 50.

Atlanta currently has 3 win(s) against Washington and 3 loss(es).
Atlanta wins 2 additional game(s) against Washington and loses 5.
Atlanta loses the series 5 games to 8.
Atlanta wins 0 additional game(s) against teams outside the division and loses 50.

Miami currently has 2 win(s) against New York and 4 loss(es).
Miami wins 7 additional game(s) against New York and loses 0.
Miami wins the series 9 games to 4.
Miami wins 0 additional game(s) against teams outside the division and loses 48.

Miami currently has 2 win(s) against Philadelphia and 5 loss(es).
Miami wins 4 additional game(s) against Philadelphia and loses 2.
Miami loses the series 6 games to 7.
Miami wins 0 additional game(s) against teams outside the division and loses 48.

Miami currently has 5 win(s) against Washington and 1 loss(es).
Miami wins 5 additional game(s) against Washington and loses 2.
Miami wins the series 10 games to 3.
Miami wins 0 additional game(s) against teams outside the division and loses 48.

New York currently has 4 win(s) against Philadelphia and 2 loss(es).
New York wins 5 additional game(s) against Philadelphia and loses 2.
New York wins the series 9 games to 4.
New York wins 0 additional game(s) against teams outside the division and loses 47.

New York currently has 5 win(s) against Washington and 2 loss(es).
New York wins 0 additional game(s) against Washington and loses 6.
New York loses the series 5 games to 8.
New York wins 0 additional game(s) against teams outside the division and loses 47.

Philadelphia currently has 4 win(s) against Washington and 2 loss(es).
Philadelphia wins 1 additional game(s) against Washington and loses 6.
Philadelphia loses the series 5 games to 8.
Philadelphia wins 0 additional game(s) against teams outside the division and loses 50.

# Atlanta Braves' magic number
# Atlanta's magic number
# Braves' magic number
# MLB Playoff Race