Western Australia (Australia) is 9,786 times larger than Seattle.
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
Area: 259 km2 calculated
Seattle is a coastal seaport city and the seat of King County, in the U.S. state of Washington. With an estimated 652,405 residents as of 2013, Seattle is the largest city in the Pacific Northwest region of North America and the fastest-growing major city in the United States. Wikipedia