Number sence What is the number?

It is greater than 43 and less than 52.
If you add the digit, the sum is 8. write the number word.

I need help figuring this out not just the answer but how to get the answer.

tens digit is 4 or 5

4+4 = 8
5+3 = 8

so 44 will work
but 53 will not work