The upper bound is 267.9 and the lower bound is 226.1.
At the beginning of the journey, the possible values of the milometer before been rounded to the nearest mile are: 43,561.5, 43,561.6, 43,561.7, 43,561.8, 43,561.9, 43,562,43,562.1, 43,562.2, 43,562.3, 43,562.4
At the end of the journey, the possible values of the milometer before been rounded to the nearest mile are: 43,828.5, 43,828.6, 43,828.7, 43,828.8, 43,828.9, 43829, 43829.1, 43829.2, 43829.3, 43829.4.
Upper bound = 43,829.4- 43,561.5 = 267.9
Lower bound = 43,828.5 - 43,562.4 = 226.1
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