|
Question 206858: A palindrome is an integer that reads the same forward and backwards. For example, 31213 is a 5 digit palindrome. How many 3 digit palindromes are even?
(A) 30 (B) 36 (C) 40 (D) 45 (E) 50
Answer by Edwin McCravy(20056)   (Show Source):
You can put this solution on YOUR website! A palindrome is an integer that reads the same forward and backwards. For example, 31213 is a 5 digit palindrome. How many 3 digit palindromes are even?
(A) 30 (B) 36 (C) 40 (D) 45 (E) 50
We are looking for numbers like 606.
The first and 3rd digits are the same, and the 3rd must be even.
The first cannot be 0, for that would amount to a 2-digit number.
So we must pick the 1st and 3rd as either 2,4, 6, or 8.
That's 4 ways.
We can pick the middle digit any of 10 ways.
That's 4*10 or 40 ways, choice (C).
Edwin
|
|
|
| |
