Question

kangaroo wants to arrange the twelve numbers from 1 to 12 in a circle in such a way that any neighboring numbers always differ by either 1 or 2 which of the following pairs of numbers have to be neighbors

Answer 1

Start by laying out the 12.
The neighbors of 12 must be 11 and 10.
The neighbor of 11 must be 9, and the neighbor of 10 must be 8, and so on and so forth, until you get a unique arrangement.