Answer: 868 miles
Step-by-step explanation:
Given: The scale from a map to actual distance is 2.5 cm to 620 miles.
i.e. 1 cm on map = [tex]\dfrac{620}{2.5}\text{ miles}=248 \text{ miles}[/tex]
If the distance on the map between Chicago and Boston is about 3.5 cm.
Then, the actual distance between them = [tex]3.5\times 248 \text{ miles}=868 \text{ miles}[/tex]
Hence, the approximate distance between Chicago and Boston = 868 miles.