Guyana is about 1.4 times smaller than Oman.

Oman is approximately 309,500 sq km, while Guyana is approximately 214,969 sq km, making Guyana 69.46% the size of Oman. Meanwhile, the population of Oman is ~5.5 million people (4.7 million fewer people live in Guyana).
Tip: This to-scale comparison of Oman vs. Guyana uses the Mercator projection, which distorts the size of regions near the poles.
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