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Dustin covered 7.26 kilometers while exercising. This is calculated by multiplying each distance in miles by 1.609 (which is the equivalence of one mile to one kilometer). Therefore, 4.5 miles * 1.609 = 7.3025 kilometers, 2.3 miles * 1.609 = 3.7277 kilometers and 3.8 miles * 1.609 = 6.1412 kilometers. Then, 7.3025 + 3.7277 + 6.1412 = 7.26 kilometers.
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