I am pretty sure that it is table one because each number from the original recipe to the teachers recipe is multiplied by three.
#1. 712.5
#2. 1185
#3 .517.5
It looks like it goes through (0,-3) and (1,2), so the gradient is (change in y)/(change in x) ->
(-3-2)/(0-1) = 5
So y=5x+b
Then as we know it passes the y axis at (0,-3) so b= -3
So we have y=5x-3
