0 faces are not painted, because 3 x 9 = 27.
If this isn't correct I don't understand.
Let's say x=cherries and y=grapes. (desmos only does x and y :( ).
the equation would be 9=4x+1.50y
I believe the answer is -2, 7
Line them all up by 100th, 10ths and Ones Place! Hope that this helps you