Answer:
7500 meters
Step-by-step explanation:
Isabella walked 2 × 2.5 km = 5 km. Together, they walked ...
2.5 km + 5 km = 7.5 km = 7.5×1000 m = 7500 m
Cole and Isabella walked 7500 meters altogether.
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"kilo-" is a prefix meaning "one thousand". So one kilometer is 1000 meters. Then 7.5 kilometers is 7.5 times 1000 meters, or 7500 meters.
