50:50

50:50 is a lifeline in the Who Wants to Be a Millionaire? game. When a contestant uses this lifeline, two of the wrong answers are removed, leaving one wrong answer and the correct one, thus giving the contestant a better chance of answering the question correctly.

In versions that include both the 50:50 and Double Dip lifelines, it is possible for a contestant to use both and automatically get the question right (most notoriously, in Who Wants to Be a Super Millionaire, although no contestant did so, but in the Russian Format, a few of them did).

Originally, using the 50:50 lifeline usually removed the two most obvious wrong answers. Later, it was turned into a random selection (a fact some hosts emphasize before the answers are removed).

Usage
The U.S. version featured the 50:50 lifeline since the show's premiere in 1999, in both primetime and during the show's first six syndicated seasons. It was discontinued after introducing the clock format at the start of the seventh syndicated season, in favor of Double Dip. However, it was reintroduced in 2015 at the start of the fourteenth syndicated season replacing the Jump the Question lifeline as part of the format revamp.

The UK version kept it until the program finished in 2014. When the UK introduced the clock, if a contestant used the 50:50, the clock would stop, and restart after the two wrong answers were removed.

Likewise, the Australian version kept this lifeline from the show's premiere in 1999 until its final episode in 2007. The 50:50 lifeline does not appear in the Hot Seat spin-off.