Guam is 50% larger than Las Vegas.
Area: 544 km2 World Factbook
Population: 161,001 (July 2014) World Factbook
Guam is an organized, unincorporated territory of the United States in the western Pacific Ocean. It is one of five U.S. territories with an established civilian government. Wikipedia
Area: 363 km2 calculated
Las Vegas, officially the City of Las Vegas and often known as simply Vegas, is the most populous city in the state of Nevada and the county seat of Clark County. Wikipedia