Answer:
12 million dollars.
Step-by-step explanation:
Let the sales in the first year be x million .
So the sales in the second year were x + 4 million, in the third year were 3(x + 4) and this is 48 million dollars.
So we have the equation 3(x + 4) = 48
3x + 12 = 48
3x = 36
x = 12 million dollars.
