District of Columbia is about 51 times smaller than Puerto Rico.

Puerto Rico is approximately 9,104 sq km, while District of Columbia is approximately 177 sq km, making District of Columbia 1.94% the size of Puerto Rico. Meanwhile, the population of Puerto Rico is ~3.1 million people (2.5 million fewer people live in District of Columbia).
Tip: This to-scale comparison of Puerto Rico vs. District of Columbia uses the Mercator projection, which distorts the size of regions near the poles.
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