SHOOTING MR. DOOR RIDDLE

Mr. Box and Mr. Door had been in the navy together years ago. They had both been on a ship that had shipwrecked in the Pacific. A group of men had survived on a liferaft but didnt have any food. Mr. Door was a navy doctor. He suggested that he would amputate each of their left arms for food. There was, however, no other doctor available to amputate Mr. Doors arm. To make it fair, Mr. Door promised that when they were back home again, he would have his arm amputated also. Mr. Door had sent Mr. Box an arm in the mail. Mr. Box assumed it was Mr. Doors arm, but when Mr. Box visited Mr. Door and saw that he still had both of his arms, he became very angry that Mr. Door had not followed through on his side of the bargain and shot him. Did you answer this riddle correctly?
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