4 fathers, 2 grand-fathers and 4 sons went to watch the movie. What is the minimum number of the tickets they need to buy? Ah! Click here to read the solution. SelectShow> The solution is 6. 2 grandfather who has two sons, are also the father of two sons( each having one son). Related Share Brain TeaserFacebookGoogle+TwitterPinterestLinkedIn Related Brain Teaser:The Cassette RecorderJanuary 18, 2018Crack The CodeJanuary 18, 2018The Crime SceneJanuary 18, 2018The ShooterJanuary 18, 2018