Question

Six identically shaped place mats, marked a, b, c, d, e and f, are piled neatly in a stack. how many arrangements are possible if a and b must touch each other?

Answer 1

6
1. A, b, c
2. A, b, d
3. A, b, e
4. C, a, b
5. D, a, b
6. E, a, b

Hope I helped!