well
let’s firstly times $2,400 by 12 which will give us $28,800 this is Roberts annual pay before a raise
than we times $200 by 12 which is $2400 which will be his raise.
Lastly we add it together which is $31,200
the equation would be (2,400 x12) + (200 x12)= 28,800 + 2400=31,200
Hope this helped :)