Question

The numbers of arrangements of the letters of the word SALOON, if the two O's do not come together, is.

• A. 360
• B. 720
• C. 240
• D. 120

Answer 1

Answer: (C)

240

Answer 2

Total number of arrangements are $\frac{6\mspace{6mu}!}{2\mspace{6mu}!} = 360$.

The number of ways in which $.... + (^{2n + 1}C_{n} +^{2n + 1}C_{n + 1})$ come together $= 5\mspace{6mu}! = 120$.

Hence required number of ways =$360 - 120 = 240$.