Abe and Sal left at the same time. They traveled in opposite directions. Sal traveled 50mph faster than Abe. After four hours, they were 400 miles apart. Find Abe's speed.

speed 1 = s

speed 2 = s + 50

total speed apart = 2 s + 50

400 miles = (2 s + 50) miles/hr * 4 hours

2 s + 50 = 100

s = 25 mph

Sal was probably speeding