The number 142,857 shown in the
diagram can be multiplied by 3 in an unusual but yet simple way. All
that is necessary is to move the 1 to the other end of the row, and
the thing is done. The answer is 428,571.
It is known there is a number that, when multiplied by 3 and divided
by 2, the answer will be the same as if we moved the first digit
(which in this case is to be a 3) from the beginning of the row to the
end. Can you guess how many digits this number consists of? Don't be
surprised by looking at the solution!