The scale is given inches/ miles equal 1/50. This means that 1 inch is equal to 50 miles.
We can use the rule of three to find the real value.
Then
1 inch --------------------------- 50miles
2.5 inches x
Where x=(2.5inch*50miles)/1 inch
x = 125 miles
For 4.75 inches​
1 inch --------------------------- 50miles
4.75 inches--------------------- x
Where x =(4.75 inch*50miles)/1inch
x = 237.5 miles