First of all, the Simpsons most likely don't live in any actual state. The city they live in is probably a combination of all the Springfields in the U.S. That is most likely why they go to specific states so easily. But, if some people don't believe me, I suggest two ways to find the state they live in. First, try watching every episode including the movie and eliminate the states they DON'T live in for sure. Or, you could do a search on the location of every DMV in the U.S. and find ones located in a Springfield. Then you might be able to find the answer.
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First of all, the Simpsons most likely don't live in any actual state. The city they live in is probably a combination of all the Springfields in the U.S. That is most likely why they go to specific states so easily. But, if some people don't believe me, I suggest two ways to find the state they live in. First, try watching every episode including the movie and eliminate the states they DON'T live in for sure. Or, you could do a search on the location of every DMV in the U.S. and find ones located in a Springfield. Then you might be able to find the answer.