Washington is about 2.7 times smaller than Papua New Guinea.

Papua New Guinea is approximately 462,840 sq km, while Washington is approximately 172,348 sq km, making Washington 37.24% the size of Papua New Guinea. Meanwhile, the population of Papua New Guinea is ~9.6 million people (2.9 million fewer people live in Washington).
Tip: This to-scale comparison of Papua New Guinea vs. Washington uses the Mercator projection, which distorts the size of regions near the poles.