From my perf manual for the for -7, -15 and -17 powered 727s...Assume a linear relationship b/t the following points, gross weight(x coord) vs density altitude (y coord), 1 pack, anti ice off, clean a/c, max cont epr:
-7: (110000 lbs, 12000 ft) and (152000 lbs, 0 ft)
-15: (110000 lbs, 16000 ft) and (170000 lbs, 0 ft)
-17: (110000 lbs, 17000 ft) and (177500 lbs, 0 ft)
With MGTOWs rangine approx from 176500 lbs - 220000 lbs, and MLW of around 155000 lbs, a 110000 lb 727 is so very light that its probably the empty a/c plus a few thousand pounds of fuel - not a very likely scenario. A crew couldn't dump/burn fuel fast enough at typical takeoff weights; the a/c is coming down, as I said.
If an -15 powered a/c left DEN
(or anywhere) weighing 175000lbs, it's max altitude at 7000 ft is 143000 lbs...A -7 powered a/c would have to weigh 127000 or less to maintain 7000 ft. Even at max dump rates, the point is that the single engine operating envelope is extremely small to the point of being unrealistic for any revenue operation.
Jhooper-this was advice, and it came off harsh...sorry.
I'm trying to encourage you to expand your knowledge base, so you are ready when the returns. There will always be more people willing to fly a/c for a living, part. 121, than there are seats available. Many CFIs are given those exact types of questions at interviews, and blow it. Knowledge is cheap; particularly when compared to experience.