Pennsylvania is about 1.5 times smaller than Oklahoma.

Oklahoma is approximately 177,847 sq km, while Pennsylvania is approximately 116,075 sq km, making Pennsylvania 65.27% the size of Oklahoma. Meanwhile, the population of Oklahoma is ~4.1 million people (8.9 million more people live in Pennsylvania).
Tip: This to-scale comparison of Oklahoma vs. Pennsylvania uses the Mercator projection, which distorts the size of regions near the poles.
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