every 10 hours of training monthly pay increases by 100
that means that for every 1 hour monthly pay increases by 10
so the answer must be in the form 10x + something
let's take the 1st row in the table
10 hours of training = 1300 monthly pay
10x+ something = 1300
10*10 + something=1300
something = 1200
therefore, monthly pay 10x +1200
hope i helped