What is nine minus x is greater than ten

This can be written as:
9-x>10
-x>1 (subtract 9 from both sides)
x<-1 (divide both sides by -1 and change the inequality sign)

Hope this helps

9-x>10
Subtract 9 from each side
-x>1
Multiply each side by -1 and reverse the inequality sign
x<-1

If i think this is what your asking, he should look at the grams or pounds/ounces and compare the to their cost then max can identify which one is proportional and which is not ( i think xd)