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A girl can shampoo the dog, clean his ears, and clip his nails in 45 minutes. I'd like to amplify a point that Stephen made. This problem is based on unrealistic assumptions! Not every task can be split among two or more people efficiently. Lewis Carroll (in his daytime personality as Charles Dodson, maths tutor at Christ Church College, Oxford), had a problem along the lines of If it takes two men ten hours to build a wall, how long would it take twelve hundred men? Students would calculate the answer as "one minute". Dodson would gently inform they that they were wrong; most of them could not even get near the wall to help! A particularly silly example of my own invention: If I can softboil an egg in three minutes, and a person in Denver, Colorado needs four minutes, how long does it take if we work together? Good Hunting!  


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