9999
ez.....9999
This is impossible. 21 is an odd number and all these digits are odd. Whenever you add 6 odd numbers together, the answer is always even!
It is 9999 (if a one is added, it becomes a five digit number: 9999 + 1 = 10,000)
There are 120 of them.
It is 9999.
9999
10001
9999
9999
Well,I know that 9999 is one number:)
ez.....9999
9999
From 1000 to 9999 (inclusive) there are 9999 - 1000 + 1 = 9000 integers. Half of which are even, half of which are odd. So the answer is 9000/2 = 4,500.
9999
9999
This is impossible. 21 is an odd number and all these digits are odd. Whenever you add 6 odd numbers together, the answer is always even!