Washington Nationals First-Place Elimination Scenario
Washington must win 16 more games (64 total) to avoid elimination from first place.
Here are the final standings in a scenario in which Washington finishes in first place with 64 wins:

Team             W	L	PCT	GB
Washington       64	98	0.395	0.00
Atlanta          63	99	0.389	1.00
Philadelphia     63	99	0.389	1.00
NYMets           62	100	0.383	2.00
Miami            62	100	0.383	2.00

To construct the scenario, we start with the current standings in the division:
Team             W	L	GL	PCT	GB
Atlanta          55	40	67	0.579	0.0
Philadelphia     54	44	64	0.551	2.5
Miami            52	45	65	0.536	4.0
Washington       48	49	65	0.495	8.0
NYMets           41	57	64	0.418	15.5

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

Atlanta currently has 5 win(s) against Miami and 2 loss(es).
Atlanta wins 5 additional game(s) against Miami and loses 1.
Atlanta wins the series 10 games to 3.
Atlanta wins 0 additional game(s) against teams outside the division and loses 42.

Atlanta currently has 3 win(s) against NYMets and 4 loss(es).
Atlanta wins 0 additional game(s) against NYMets and loses 6.
Atlanta loses the series 3 games to 10.
Atlanta wins 0 additional game(s) against teams outside the division and loses 42.

Atlanta currently has 5 win(s) against Philadelphia and 1 loss(es).
Atlanta wins 3 additional game(s) against Philadelphia and loses 4.
Atlanta wins the series 8 games to 5.
Atlanta wins 0 additional game(s) against teams outside the division and loses 42.

Atlanta currently has 4 win(s) against Washington and 3 loss(es).
Atlanta wins 0 additional game(s) against Washington and loses 6.
Atlanta loses the series 4 games to 9.
Atlanta wins 0 additional game(s) against teams outside the division and loses 42.

Miami currently has 3 win(s) against NYMets and 3 loss(es).
Miami wins 3 additional game(s) against NYMets and loses 4.
Miami loses the series 6 games to 7.
Miami wins 0 additional game(s) against teams outside the division and loses 39.

Miami currently has 2 win(s) against Philadelphia and 5 loss(es).
Miami wins 6 additional game(s) against Philadelphia and loses 0.
Miami wins the series 8 games to 5.
Miami wins 0 additional game(s) against teams outside the division and loses 39.

Miami currently has 5 win(s) against Washington and 1 loss(es).
Miami wins 0 additional game(s) against Washington and loses 7.
Miami loses the series 5 games to 8.
Miami wins 0 additional game(s) against teams outside the division and loses 39.

NYMets currently has 3 win(s) against Philadelphia and 4 loss(es).
NYMets wins 5 additional game(s) against Philadelphia and loses 1.
NYMets wins the series 8 games to 5.
NYMets wins 0 additional game(s) against teams outside the division and loses 39.

NYMets currently has 3 win(s) against Washington and 4 loss(es).
NYMets wins 6 additional game(s) against Washington and loses 0.
NYMets wins the series 9 games to 4.
NYMets wins 0 additional game(s) against teams outside the division and loses 39.

Philadelphia currently has 5 win(s) against Washington and 2 loss(es).
Philadelphia wins 4 additional game(s) against Washington and loses 2.
Philadelphia wins the series 9 games to 4.
Philadelphia wins 0 additional game(s) against teams outside the division and loses 39.

# Washington Nationals' magic number
# Washington's magic number
# Nationals' magic number
# MLB Playoff Race