+610 Find the total number of four-digit palindromes. (Recall that a palindrome is a nonnegative sequence of digits which reads the same forwards and backwards, such as 1331. Zero cannot be the first digit.)
+981 There are two methods to do this problem.
Method 1: Pattern Finding
There are 9 palindromes with 2 digits
There are 90 palindromes with 3 digits
There are 90 palindromes with 4 digits
Method 2: Counting
The 4 digit palindrome is in this format:
ABBA
There are 9 choices for A
10 for B
9*10=90
I hope this helped,
Gavin
