I had presumed in my earlier answer that the hobbit and elf would start with their feet outside the land to measure each pace from the front of one footprint to the front of the next.
But if their first footprint was inside the plot of land then they were measuring from the rear of their first footprint to the rear of the next one.
Therefore after the hobbit had made 41 steps, including the first step at zero (and the elf had made 31 steps including the first step at zero, only 20 of which would not coincide with the hobbit’s), the measurement to the back of their final footprint would be 2160, so if this footprint (number 61) is to be included, then the total would be anything between (2160 + the length of the last footprint) and 2214 which would be where the next hobbit footprint (which would be number 62 so is not within the plot of land) would be.

However, several of our longtime regular readers have excellent explanations you can check out above.

You can find a short pattern with a simple chart by measuring step by step and find that for every 4 steps the hobbit takes the elf 3 steps. That final step corresponds to two foot prints. Thus leaving 6 foot prints on the ground. This pattern repeats until a total of 60 footprints are made afterwhich the hobbit took 40 steps and the elf took only 30 both of which add up to 2160 cm.

And here’s the rub, where did footprint 61 come from………. the starting point.

I really have to do a better job proofing my own work before I submit. I think I’m starting to lose it in my old age.

The overlapping footprints occur every 216 cm, because 216 is the least common multiple of 54 and 72. Every 216 cm, the hobbit walks 4 paces and the elf walks 3 paces. For every 216 cm, what you see on the ground is 3 hobbit prints, 2 elf prints, and one print where they overlap. So every set of 6 prints corresponds to 216 cm paced off.

If they both started at the inside edge of the plot of land, then print #1 is an overlap, as are prints 7, 13, 19, 25, and so on to print 61. This means that they paced off 216 cm a total of 10 times, for a distance of 2160 cm.

Disclaimer: There are a few assumptions I chose to make, because they led to an exact answer, rather than an indefinite range.

The first is that they started inside the plot of land. If they started outside, then the overlaps are at prints 6, 12, 18, and so on to print 60. The last print would be from the hobbit, and the plot of land is somewhere between 2214 cm and 2232 cm long.

The second is that, if one’s left foot and the other’s right foot correspond to the same distance, it would be considered an overlap, rather than two prints side by side. If the latter is the case, then there would be 13 prints every 432 cm instead. If they both started inside the plot of land and both started off with the same foot, the overlaps would be at prints 1, 14, 27, 40, and 53, covering the first 1728 cm. There would be 5 additional hobbit prints and 3 additional elf prints, making the total distance somewhere between 2318 cm and 2336 cm in length.

Sorry that the disclaimer is longer than the original solution, but sometimes that’s the price you pay for a complete answer.

54cm long step:

40 steps × 54 cm = 2160 cm

72cm long step:

72 steps × 30 steps = 2160 cm

That is 60 steps only.

The 60th step will come from the guy with shorter steps;

so, 2160 + 54 = 2214 = 22.14 meters

3*72 = 4*54

elf-steps:
0 3 6 9 12 15 18 21 24 27 30
hobbit steps:
0 4 8 12 16 20 24 28 32 36 40

step “0″ still leaves a print

31 + 41 = 72 possible footprints
72 – 11 matching footprints = 61 visible footprints

30 elf-steps = 30*72cm = 2160cm
or
40 hobbit-steps = 40*54cm = 2160cm