There are two routes Lucas can take to walk to school. Route A is 2 and StartFraction 1 over 8 EndFraction miles and is StartFraction 3 over 8 EndFraction mile longer than route B. The equation b + StartFraction 3 over 8 EndFraction = 2 and StartFraction 1 over 8 EndFraction can be used to represent this situation, where b is the length of route B. How many miles will Lucas walk if he takes route B?