Thomas has some leftover paint that he would like to sell. He mixes 4 3 8 gallons of blue paint with 6 1 8 gallons of white paint. Then, he pours this light-blue mixture into 1 4 gallon containers. How many of these 1 4 gallon containers can he fill completely with this paint mixture?

First, we need to add the total amount of blue and white paint Thomas has:

4 3/8 gallons + 6 1/8 gallons = 10 4/8 gallons + 6 1/8 gallons = 16 5/8 gallons

Next, we convert this to a mixed number:

16 5/8 = 16 + 5/8 = 16 10/16 + 5/8 = 16 15/16 gallons

Now, we divide the total amount of paint by the amount that can fit in each container:

16 15/16 gallons ÷ 1/4 gallon/container = 67 containers

Therefore, Thomas can completely fill 67 of the 1/4 gallon containers with his paint mixture.