Start with what you know or what you have been given. That 1 2/5 mile is equal to 5/8 of the total.
Write this using numbers and convert the mixed number to an improper fraction.
7/5 = 5/8 X
Multiply both sides of the equation by 8/5
7/5 * 8/5 = 5/8 * 8/5 * X
56/25 = X
2 6/25 = X