Missoula is about 2.4 times smaller than Seattle.

Seattle is approximately 217 sq km, while Missoula (map shows its 17 named neighbourhoods; the area covers the whole city) is approximately 91 sq km, making Missoula 41.75% the size of Seattle.
Tip: This to-scale comparison of Seattle vs. Missoula uses the Mercator projection, which distorts the size of regions near the poles.
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