40. Excluding numbers starting with 0.
There are lots of them: one such is 2304.
-200
Not sure what you're asking, but here are some examples of numbers that have a tens digit less than the ones digit: 13, 205, 1367, 29.632
While I'm tempted to tell you to do your own homework, this is intriguing enough that I'm willing to spend some time helping you to work it out.First: by four digit palindromes that means numbers of the form ABBA.A is constrained by "less than 5000". A can only be 0, 1, 2, 3, or 4, because otherwise ABBA would be greater than 5000 (the lowest possible ABBA number where A is 5 or greater is 5005 ... which is over 5000).A is further constrained by "4 digit". It can't be 0, because by convention we don't write leading zeroes and then ABBA would only be a three digit number.So A can be 1, 2, 3, or 4 (4 distinct possibilities).There are no constraints on B. It can be any digit (including 0), which means there are 10 distinct possibilities.Since once we specify both A and B we're done, that means there are (4 possibilities for A) x (10 possibilities for B) = 40 four-digit palindromes less than 5000.
There are 278 5-digit numbers less than 20,000 that are divisible by both four and nine.
It is 77.It is 77.It is 77.It is 77.
What is the greatest palindromic number less than 999?
There are lots of them: one such is 2304.
-200
anywhere from 4001-4999
While I'm tempted to tell you to do your own homework, this is intriguing enough that I'm willing to spend some time helping you to work it out.First: by four digit palindromes that means numbers of the form ABBA.A is constrained by "less than 5000". A can only be 0, 1, 2, 3, or 4, because otherwise ABBA would be greater than 5000 (the lowest possible ABBA number where A is 5 or greater is 5005 ... which is over 5000).A is further constrained by "4 digit". It can't be 0, because by convention we don't write leading zeroes and then ABBA would only be a three digit number.So A can be 1, 2, 3, or 4 (4 distinct possibilities).There are no constraints on B. It can be any digit (including 0), which means there are 10 distinct possibilities.Since once we specify both A and B we're done, that means there are (4 possibilities for A) x (10 possibilities for B) = 40 four-digit palindromes less than 5000.
Not sure what you're asking, but here are some examples of numbers that have a tens digit less than the ones digit: 13, 205, 1367, 29.632
18 numbers are there
40, 51, 62, 73, 84, and 95
The ones digit in the product from multiplying the 305 prime numbers less than 2012 is 0 because the ones digit becomes 0 after 2 and 5 have been multiplied and remains unchanged after more prime numbers are multiplied.
There is no limitation given to the number of digits in the number, thus: For 3 digit numbers: to be less than 500 the first digit can be only one of {1, 2, 3, 4} leading to 4 × 5 × 4 = 80 numbers For 2 digit numbers: they are all less than 500, and there are 6 × 5 = 30 numbers For 1 digit numbers: they are all less than 500, and there are 6 numbers Thus there are in total 80 + 30 + 6 = 116 numbers that can be made form the digits {1, 2, 3, 4, 5 ,6} without repetitions that are less than 500.
11,31,41