Scale question

Question

The distance from Boston to New York is 216 miles.  On a map, 1/4 inch represents 20 miles.  How many inches is it from Boston to New York on the map?

Answer 1

You can set up a proportion:

 

1/4 inch   =     _ X         

20 miles          216 miles

 

Cross multiply:  (1/4 inch)*(216 miles) = x * (20 miles)

Combine & Cancel:  1/4*216 inches*miles = 20*x miles

Finish:  54  inches = x

           20

 

x = 2.7 inches