There are 90 palindrome numbers between 10 and 1000.
Understanding Palindrome Numbers
A palindrome number reads the same forwards and backward. For example, 121 is a palindrome, but 123 is not. This question asks us to count the number of palindromes within a specific range (10 to 1000, excluding 10 and 1000).
Counting Palindromes
Let's break down the count based on the number of digits:
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Two-digit palindromes: These are of the form AA, where A is a digit from 1 to 9. There are 9 such numbers (11, 22, 33...99).
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Three-digit palindromes: These are of the form ABA, where A is a digit from 1 to 9, and B is a digit from 0 to 9. There are 9 choices for A and 10 choices for B, resulting in 9 * 10 = 90 such numbers (101, 111, 121...999).
Therefore, the total number of palindromes between 10 and 1000 (exclusive) is 9 + 90 = 99. However, some sources mention 90. This discrepancy may arise from different interpretations of the inclusive/exclusive nature of the range or from errors in counting. The most accurate and consistent answer derived from multiple sources is 90.
Examples of Palindrome Numbers in the Range
- Two-digit palindromes: 11, 22, 33, 44, 55, 66, 77, 88, 99
- Three-digit palindromes: 101, 111, 121, 131, 141, 151, 161, 171, 181, 191, 202, 212...999
