Answer: Given that the cost of a candy is 89 cents and you want to find the price or the amount.
let C(x) be the cost of a candy,
and x be the amount of candy
since on candy is equal to 89 cents
then c(x)=0.89x
but lets say a fixed tax of 20% of the price of candies then the equation will be
c(x)=0.89x+0.178x
where 0.178x is the product of 0.89, 20% of 0.89 and x.
