+0  
 
0
224
5
avatar

A $\textit{palindrome}$ is a number which reads the same forward as backward, for example 313 or 1001. Ignoring the colon, how many different palindromes are possible on a 12-hour digital clock displaying only the hours and minutes? (Notice a zero may not be inserted before a time with a single-digit hour value. Therefore, 01:10 may not be used.)

 Aug 5, 2020
 #1
avatar+111547 
+1

3 digits,

chose the first digit 9 choices      1,2,3,4,5,6,7,8,9

Chose the second 6 choices    0,1,2,3,4,5

chose the third, it has to be the same as the first so 1 choice

9*6*1=54 ways

 

Thanks for the correction EP.

 

4 digits

you can do this one yourself.

 Aug 5, 2020
edited by Melody  Aug 5, 2020
 #2
avatar+28021 
+1

Yikes....   the second digit can only go as high as 5 ....cheeky

ElectricPavlov  Aug 5, 2020
 #3
avatar+111547 
0

thanks EP :)

Melody  Aug 5, 2020
 #4
avatar+169 
0

Wait why is that?

OooOOh because we're on a clock? okie

Inspirational  Aug 6, 2020
edited by Inspirational  Aug 6, 2020

11 Online Users