Guinea is about 1.5 times smaller than Montana.

Montana is approximately 376,979 sq km, while Guinea is approximately 245,857 sq km, making Guinea 65.22% the size of Montana. Meanwhile, the population of Montana is ~989,415 people (12.2 million more people live in Guinea).
Tip: This to-scale comparison of Montana vs. Guinea uses the Mercator projection, which distorts the size of regions near the poles.
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