How do you do letter equations?

Question

"Each letter in the equation below represents a different digit from the set (1, 3, 4, 7, 8). find the value of each letter to make the equation true. Each letter must represent only one number throughout the entire problem."

A D D
+ M A D
---------
S U M

Answer 1

well, D+ D= M and maybe a carry digit. From your choices, D has to be 3, and M is 8.
Then D+A=U or 4+A=U with maybe a carry digit if A is 7, or 8
Now finally, A+M=S with no carry digit.
A+8=S so that means M has to be 1, and S...
You finish it.

Answer 2

ummmm....... I came to website bc I have a question for you to answer for me!