In how many 6 digit numbers can be formed using the digits 1 to 5(repetitions allowed) such that the number reads the same from left to right or from right to left(e.g. 134431)?
a)5^6 b)5^3 c)5^2 d)5^10

• since repetition is allowed: possibilities for
  pos1=5, pos2=5, pos3=5 and pos4=pos3, pos5=pos2, pos6=pos1
  
  therefore, ans 5*5*5 = 5^3
• 7 years agoHelpfull: Yes(0) No(1)