If you are assuming 0 to be an even digit:
If 0 is not to be used as an even digit, it is completely different.
201
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298
You said "between" so I left out 300.
17
two
There are 41 of them.
The sum of the number of digits in all the numbers between 31 and 400 inclusive is 1041.
Counting all integers from 1 to 238 inclusive, there are 606 digits between these two numbers.
17
two
There are 6484 digits BETWEEN the two given numbers.
223
123
There are 41 of them.
Five... 0,2,4,6 & 8
There are 5760 such numbers.
The number is: 36725918 In descending order that is: 98765321 The pairs of numbers that have as many digits between them in both are: 3,9 5,8 6,7 So there are three pairs.
The sum of the number of digits in all the numbers between 31 and 400 inclusive is 1041.
500
I believe here are 51 such numbers.