Total number of $n$ digit numbers $(n 1)$ having the property that no two consecutive digits are same, is

Question

Total number of $n$ digit numbers $(n > 1)$ having the property that no two consecutive digits are same, is

Dr. Abubacker · Accepted Answer

(b)
Diagram
The digit $x_{1}$can be selected in 9 ways as 0 cannot be selected. The digit $x_{2}$ can be selected in 9 ways as 0 can selected but digit in position $x_{1}$ cannot be selected. Similarly, all the remaining digits can also be selected in 9 ways.
Hence, total number of ways $= 9^{n}$

Q. Total number of $n$ digit numbers $(n > 1)$ having the property that no two consecutive digits are same, is

Explanation

Reviewed by Dr. Abubacker

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