South Australia is about 1.6 times smaller than Quebec.

Quebec is approximately 1,542,056 km² (595,391 sq mi), while South Australia is approximately 984,321 km² (380,048 sq mi), making South Australia 63.83% the size of Quebec.
Tip: This to-scale comparison of Quebec vs. South Australia uses the Mercator projection, which distorts the size of regions near the poles.
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