Multiple choice general knowledge math & puzzles

Boxes numbered 1, 2, 3, 4, and 5 are kept in a row, and they are to be filled with either a red or a blue ball, such that no two adjacent boxes can be filled with blue balls. How many different arrangements are possible, given that all balls of a given colour are exactly identical in all respects?

  1. 8

  2. 10

  3. 15

  4. 22

Reveal answer Fill a bubble to check yourself
D Correct answer