Math Riddles

Answer: They will be the same distance away when they meet.

Answer: The said number has all the numbers from 0-9 exactly once and what is special is they are in lexicographical order of their English words. Where 8,549,176,320 becomes eight-five-four-nine-one-seven-six-three-two-zero. ... The number contains all the digits from 0 to 9.

Answer: If they are round the manhole covers cannot slip into the hole if the hole is slightly smaller than the cover, but if they are square the hole would have to be about 50 percent of the area of the cover to stop the cover from falling into the hole (diagonally).

Answer: Count the letters in every number. (etc. one [o-n-e{3 letters}] 3 [t-h-r-e-e] 5 [f-i-v-e] 4 [f-o-u-r] four has the same amount of letters in it).

Answer: 14.