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2 votes
2. A palindrome is a number or a word that is the same in the two directions: left to right and vice

versa. Example of palindromes: dad, mom, noon, karak, 22, 121, 3443. How many palindrome
numbers can you make with 4 digits, with the possibility of repeating the digits? *
*8100
*8102
*8104
*8098

User Hong Tang
by
6.5k points

1 Answer

2 votes

Answer:

90 between 1000 and 9999

Explanation:

The first digit cannot be 0. It can be nine other digits.

The second digit can be anything between 0 and 9.

To be palindromic the 2nd and 3rd digits must be the same.

And in addition, the 1st and 4 numbers must be the same.

So the answer is 9 * 10 = 90. That does seem too small, but try making a palindrome with the restrictions I have outlined. None of the examples you have given beginning with 8 are palindromic.

8118 is palindromic

8998 is also palindromic

9009 is palindromic

2002 is palindromic

There are only 90 of them.

User Igor Gladun
by
6.7k points
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