South Dakota is about 1.4 times smaller than Nevada.

Nevada is approximately 284,448 sq km, while South Dakota is approximately 196,540 sq km, making South Dakota 69.1% the size of Nevada. Meanwhile, the population of Nevada is ~2.7 million people (1.9 million fewer people live in South Dakota).
Tip: This to-scale comparison of Nevada vs. South Dakota uses the Mercator projection, which distorts the size of regions near the poles.
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