Real age of Rihanna in The Hangover
In the movie The Hangover, Rihanna was:
20 years old
That was the real age of the celebrity according to our calculation.
The calculation of the shown age took into account the first day of the year in which the movie The Hangover was released:
January 1, 2009
And the day in which Rihanna was born:February 20, 1988
Since movies usually don't take more than one year to be released since the beginning of the filming process, Rihanna may have been one year younger or one year older than the shown age while some scenes of the movie were being filmed.