Question

one number is thrice the other and their sum 112

Answer 1

one number=x
other number=3x
so,x+3x=112
4x=112
x=112/4
x=28

Answer 2

let two no. be x and y
now x=3y
and x+y=112
so 3y+y=112
    y=28
now  x=3y
so   x=3*28
         =84