At 12:00 noon, Lunis started driving from Columbus to Cincinnati at a steady 40 mph. Fifteen minutes later, at 12:15, Ethan started driving from Cincinnati to Columbus at a steady 50 mph. The two cars passed each other at a point midway between the two cities. Using this information, calculate the distance between Columbus and Cincinnati. (Is this distance correct?)

So the distance each drove:
L = 40 x 1.25 = 50
E = 50 x 1 = 50
E = 50 x 1 = 50
So according to the problem, Cincinnati and Columbus are 100 miles apart.
BUT according to the atlas, they’re really 109 miles apart. So how fast were Lunis and Ethan really going?