The Grey Labyrinth is a collection of puzzles, riddles, mind games, paradoxes and other intellectually challenging diversions. Related topics: puzzle games, logic puzzles, lateral thinking puzzles, philosophy, mind benders, brain teasers, word problems, conundrums, 3d puzzles, spatial reasoning, intelligence tests, mathematical diversions, paradoxes, physics problems, reasoning, math, science.

This one is best done in Excel to work out the math. The
answer is 21 times in line A and 20 times in line B for a total time of 1094
minutes each.The trick to solving this
correctly is to realize that the person who stands in the corner of each
hallway actually shows up in both the vertical and horizontal corridors.
Without this assumption, lines A & B do not even converge on an exact time.

II) Lateral – The Day
Off

He wasn’t taking a day off from work, but rather a day off
from “working out” either training or doing some exercise routine.

III) Converting The
Series

The simple sequence to convert is just 1,2,3,4,5..etc

Writing them as full words you get:

One

Two

Three

Four

Five

Six

Seven

Eight

The converted series is the Roman numeral value spelled in
each word…if one exists. (ie. SIX = 9) The number ELEVEN has L and V separated
though, and the fix is to multiply when this happens (ie. 50x5 = 250).

The next time this happens is thirty-five with I and IV. As
the puzzle stated “the problem is just like the last one”

1x4 = 4, which is 14 iterations away (around a dozen)

The no-prefix measurement is missing, but really it can’t be
included so “nothing” is missing.They
are all the metric prefixes for all forms of measurement.