Question

the scale from a map to actual distance is 2.5 cm to 620 miles the distance on the map between Chicago and Boston is about 3.5 cm what is the distance between Chicago and Boston​

Answer 1

868 miles

Explanation:

cm to miles ? are you sure you got the problem description right ? because cm are part of the metric system (mm, cm, meters, kilometers), while miles are part of American/ UK systems. and they don't deal with cm.

but ok, so, we will not deal with conversion rates, we will just apply the scale factors.

2.5 cm <-> 620 miles

3.5 cm <-> ? miles

that is determined by the factor to go from 2.5 to 3.5 cm. the same factor then had to be applied to the miles.

2.5 × f = 3.5

f = 3.5 / 2.5 = 7/2 / 5/2 = 7/2 × 2/5 = 7×2 / 2×5 = 7/5

=>

620 × 7/5 = 868 miles