Answer: The combined amount of raisin and oatmeal cookies sold=80.
Explanation:
Let x be the combined amount of raisin and oatmeal cookies sold
Given:-
Amount of raisin cookies sold=72
The ratio of raisin cookies sold to oatmeal cookies sold = 9:1
Thus Amount of raisin cookies sold =

Therefore, the combined amount of raisin and oatmeal cookies sold=80.