The correct answer is X = 13! I don’t know how to explain but I am 100% that is the correct answer!
1.46 points put them all in to decimals so 4.26-3.5= .76 + .7 is 1.46
A=$20.20/10gal=$2.02 per gal
B=$26.04/12gal=$2.17 per gal
C=$28.14/14gal=$2.01 per gal
D=$30.45/15gal=$2.03 per gal
So C is the cheapest per gallon.