-1000
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
19
2800
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There are 40 palindromes that are divisible by 25
There are 900 6-digit palindromes.
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
1900