Western Australia (Australia) is 2.1 times larger than South Africa.
Area: 1,214,470 km2 World Factbook
Population: 48,375,645 (July 2014) World Factbook
South Africa, officially the Republic of South Africa, is a country located at the southern tip of Africa. It has 2,798 kilometres of coastline that stretches along the South Atlantic and Indian oceans. Wikipedia
Western Australia is a state occupying the entire western third of Australia. It is bounded by the Indian Ocean to the north and west, the Great Australian Bight and Southern Ocean to the south, the Northern Territory to the north-east and South Australia to the south-east. Wikipedia