Question

Consider the following ordered string of pebbles of three colors, green (G), blue (B) and red (R) :
X = GGBRBRRBBR
Y = GBRRBRBBRG
Z = RBBRGGBRBR
Which two of them will give us identical necklaces prepared by just making the first and the last pebbles of the string adjacent?

1. X and Y
2. Y and Z
3. X and Z
4. No two of them are identical

Answer 1

Correct Answer - Option 3 : X and Z

Detailed solution:

Rearranging Y and Z, 

X = GGBRBRRBBR
Y = GGBRRBRBBR
Z = GGBRBR RBBR

Here we can see that when Y and Z are arranged so that all start in the same pattern (i.e. with GG), only X and Z follows the same pattern

∴ X and Z will give use identical necklaces by making the first and last pebbles adjacent