2000.The smallest four-digit number there can be is 1000. So, add 1000 and 1000 to get 2000, then least sum you can get when adding two four-digit numbers.
Add the two greatest possible four digit numbers. 9999 + 9999
Greatest = 9,999Smallest = 1,008
1000, 1004, 1008, 1112 and just keep adding four until you get to 9996.
the greatest four digit number is 9999
1023, 1056 and just keep adding 33 until you get to 9999
The greatest place value will be whatever non-zero digit is farthest to the left. Look at the digit immediately to the right of it. If that digit is four or less, zero it and everything to the right of it out. If that digit is five or higher, increase the greatest digit by one and zero everything to the right of it out.
Lowest four-digit number: 1000 Highest four-digit number: 9999
9,999,876 is the greatest seven-digit number using four different digits.
7000 - 999 ie 6001 four digit numbers