Question 1033817
Draw this.
The hypotenuse of the right triangle is the square root (45^2)+(60^2)=square root of 2025=3600=square root of 5625, or 75 miles.
If you divide 45 and 60 by 15, you get 3 and 4, and the hypotenuse is 5.  Multiply that by 15 and get 75.