The article states "With the sale to Landry's, Poster and Breitling will have tripled their combined initial equity investment of about $50 million in the year or so since they purchased both Golden Nugget casinos in Las Vegas and Laughlin from MGM Mirage for $215 million"

Their share was therefore approx 23%. Plans are to sell for $295m + $31m. 23% of this is $75m

Looks a 50% increase, not a tripling?