Question

111=13
115=57
121=14
512=!

Answer 1

the answer is 28
111=13
as 1+1+1=3 and the last digit is 1
so the 111=(last digit)(sum of digits)=(1)(3)=13
similarly
115=(last digit)(sum of digits )=(5)(1+1+5)=57   (representation not multilplication)
so 512=(last digit)(sum of digit )=(2)(5+1+2)=28

Answer 2

the answer is 28 because the logic for the question is is the last digit of the no.s before equal to and the sum of digits.
hope this helps u!!!!