For the 3 digit numbers from 900 - 999 then the 1st and 3rd numbers must be 9. The middle digit can vary from 0 - 9 making 10 palindromes in this range.
For the 4 digit numbers from 1000 to 1900 then the 1st and thus the 4th digit can only be 1. The middle pair of digits must be identical and can vary from 00 to 88 making 9 palindromes in this range.
Note : 1991 is outside the permitted range.
In total there are thus 10 + 9 = 19 palindromes between 900 - 1900.
The palindromic numbers between 900 and 1900 are:909919929939949959969979989999100111111221133114411551166117711881This is a total of 19 numbers.
There are 900 6-digit palindromes.
1900
900 This explains it. A positive integer is a palindrome if it reads the same forward and backwards such as 1287821 and 4554. Determine the number of 5-digit positive integers which are NOT palindromes. We start by counting the total number of 5 digit positive integers. The first digit is between 1 and 9, so we have 9 choices. Each of the other 4 digits can be anything at all (10 choices for each). This gives us 9(10)4 = 90000 five-digit positive integers. Now we need to count the number of 5 digit palindromes. Again, we have 9 choices for the first digit and 10 choices for each of the next two. The tens and units digits however are fixed by our choices so far. Therefore, there are only 900 five-digit palindromes. Therefore, the total number of five-digit positive integers which are not palindromes is 90000-900 = 89100.
1-digit: 9 2-digit: 9 3-digit: 9 x 10 = 90 4-digit: 9 x 10 = 90 5-digit: 9 x 10 x 10 = 900 6-digit: 9 x 10 x 10 = 900
The palindromic numbers between 900 and 1900 are:909919929939949959969979989999100111111221133114411551166117711881This is a total of 19 numbers.
19
2800
2800
There are 40 palindromes that are divisible by 25
There are 900 6-digit palindromes.
1900
For there to be palindromes, each digit must be replicated. Therefore there are at most three distinct digits.If there are 3 pairs of different digits, then there are 6 palindromes. If there can be more duplicate digits, then there are 27 palindromes.
899100 of them. Only 900 of the 900000 are palindromic.
2800
It is 1900 lbs in lbs.
Basically, the difference lie on the frequency being used or supported. For GSM dual band phones, the frequencies that is can support are 900/1800 MHz or 850/1900 MHz; for tri-band phones, the frequencies are 850/1900/2100 or 850/1700/2100 or 900/1900/2100 MHz or 900/AWS/2100; and for quad-band phones, the frequencies are 850 / 900 / 1800 / 1900