Question: The Grand Victoria Casino Elgin is 50% owned by a subsidiary of a company which acquired Mandalay Resort Group, what percent of CityCenter in Las Vegas does this company own?

Context paragraphs:
Mandalay Bay Tram: The Mandalay Bay Tram is a 838 m long people mover that opened on April 9, 1999 on the Las Vegas Strip in Paradise, Nevada.  It was constructed to connect three gaming hotels belonging to the MGM Mirage Group.  The line carries passengers from the major Tropicana – Las Vegas Boulevard intersection, via the Excalibur Hotel and Casino and Luxor Hotel to the Mandalay Bay Resort and Casino at the southern end.

Encore Las Vegas: Encore Las Vegas (also called Encore at Wynn Las Vegas; often just called Encore) is a luxury resort, casino and hotel located on the Las Vegas Strip in Paradise, Nevada.  The resort is connected to its sister resort, Wynn Las Vegas; both are owned by Wynn Resorts, headed by casino developer Steve Wynn.

CityCenter: CityCenter (also known as CityCenter Las Vegas) is a 16797000 sqft mixed-use, urban complex on 76 acre located on the Las Vegas Strip in Paradise, Nevada.  The project was started by MGM Resorts International; Dubai World became a joint partner during the project's construction phase.  It is the largest privately funded construction project in the history of the United States.  The project is connected by a people mover system to adjacent MGM properties Monte Carlo Las Vegas and Bellagio Las Vegas.  As of 2015, the "CityCenter" branding has been largely retired, with the focus instead on the Aria brand of the development's centerpiece property in names such as the "Aria Express" (formerly "CityCenter Tram") and "Aria Art Collection" (formerly "CityCenter Art Collection").

MGM Resorts International: MGM Resorts International is a global hospitality and entertainment company operating destination resorts in Las Vegas, Mississippi, New Jersey and Detroit, including Bellagio, MGM Grand, Mandalay Bay and The Mirage.  The company recently opened MGM National Harbor in Maryland and is developing MGM Springfield in Massachusetts.  It has a majority interest in MGM China Holdings Limited, which owns the MGM Macau resort and casino and is developing a gaming resort in Cotai.  MGM Resorts owns 50 percent of CityCenter in Las Vegas, which features ARIA Resort & Casino.  It has a majority controlling interest in MGM Growth Properties, a real estate investment trust.

Las Vegas Uncork'd: Las Vegas Uncork'd (also referred to as Vegas Uncork'd and Vegas Uncorked) is an annual culinary and wine event in Las Vegas, Nevada.  The concept was developed by the Las Vegas Convention and Visitors Authority, their advertising agency R&R Partners and Las Vegas resort partners who originally considered a number of magazine partners such as Bon Appetit, Food & Wine and Gourmet.  Bon Appetit was selected as the magazine partner after a review with each magazine.  The event was launched in 2007 by the Las Vegas Convention and Visitors Authority, "Bon Appétit" magazine led by Editor-in-Chief Barbara Fairchild and co-creator and Executive Director Rob O'Keefe who led the first five years of development of what Eater.com called "the world's most innovative culinary event".  Las Vegas resort partners over the years include Bellagio, Caesars Palace and Wynn Las Vegas, MGM Grand, Mandalay Bay, The Venetian, Las Vegas and The Palazzo and each year the event features more than 80 celebrated chefs and over 25 events occurring over a spectacular four-day weekend.

Corey I. Sanders: Corey Sanders has served as Chief Operating Officer of MGM Resorts International since June 2010.  He oversees operations at the Company’s wholly owned properties, which in Nevada include Bellagio (resort), MGM Grand Las Vegas, Mandalay Bay, The Mirage, New York-New York Hotel and Casino, Monte Carlo Resort and Casino, Luxor Las Vegas, Excalibur Hotel and Casino, Circus Circus Las Vegas, Circus Circus Reno, Gold Strike Jean and Railroad Pass Casino.  He also oversees Beau Rivage (Mississippi) in Biloxi and Gold Strike Tunica, both in Mississippi, as well as MGM Grand Detroit.

Rising Star Casino Resort: Rising Star Casino Resort (previously the Grand Victoria Casino & Resort) is a riverboat casino and hotel in Rising Sun, Indiana, USA, owned and operated by Full House Resorts.

Aria Resort and Casino: Aria Resort and Casino is a luxury resort and casino, part of the CityCenter complex on the Las Vegas Strip in Paradise, Nevada.  Aria consists of two curved glass and steel highrise towers adjoined at the center.  It opened on December 16, 2009 as a joint venture between MGM Resorts International and Infinity World Development.  At 4000000 sqft and 600 ft in height, it is the largest and tallest structure at CityCenter.

Mandalay Resort Group: Mandalay Resort Group (formerly Circus Circus Enterprises) was a hotel-casino operator based in Paradise, Nevada.  Its major properties included Mandalay Bay, Luxor, Excalibur and Circus Circus, as well as half of the Monte Carlo.  In terms of market capitalization, it was one of the largest casino operators in the world.  Its stock traded on the New York Stock Exchange with the ticker symbol "CIR" and "MBG".

Grand Victoria Casino Elgin: The Grand Victoria Casino Elgin is a riverboat casino in Elgin, Illinois, United States, located about 40 mi west of Chicago.  It is 50% owned and operated by RBG, LLP, a subsidiary of Hyatt, and 50% by a subsidiary of MGM Resorts International, which acquired Mandalay Resort Group, the former 50% partner company, in April 2005.

Supporting paragraphs: Grand Victoria Casino Elgin MGM Resorts International
Answer: 50 percent