Marla begins walking at 3 mi/h toward the library. Her friend meets her at the halfway point and drives her the rest of the way to the library. The distance to the library is 4 miles. How many hours did Marla walk?
First, I set up an equation, 3(h+.5)=4h. Then I simpilified it to 3h+1.5=4h. I divided 1.5 by 1h. I got h=1.5. Is this right?