Cracked 'THAT' Logic!
Or look at the question first!
Let's have a look at the given equations once again.
1 1 1 1 = R
2 2 2 2 = T
3 3 3 3 = E
4 4 4 4 = N
If rewritten after adding numbers & addition is spelled then,
1 1 1 1 = FOUR
2 2 2 2 = EIGHT
3 3 3 3 = THREE
4 4 4 4 = SIXTEEN
Clearly, last letter of spelling is taken.
Hence,
5 5 5 5 = TWENTY
5 5 5 5 = Y
