2016 · Q17
A palindrome is a number which reads the same from left as well as right, for example, 23732, what is the number of palindromes between 10 and 1010?
General Mental Ability, Quantitative Aptitude and StatisticsNumber system and arithmetic
- A101
- B100
- C99
- D90
Explanation
Two-digit palindromes (11…99): 9. Three-digit palindromes (101…999): 9 choices for the outer digit × 10 for the middle = 90. Four-digit palindromes below 1010: only 1001, i.e. 1. Total = 9 + 90 + 1 = 100. Hence (B).