Run Walk Combo - 4 miles

After taking a break for a few days due to a cold, I completed a run walk combo:

Mile 1:  All walk = 13:49/mile
Mile 2: 50% walk, 50% run = 11:03
Mile 3: 40% walk, 60% run = 10:19
Mile 4: 20% walk, 80% run = 9:01
Mile 4.2: All run = 8:09/mile.

Average pace 10:56. So, if I repeat this strategy at the marathon, I will complete the marathon in about 4:45.