Please answer correctly

answer: hence, function will be

explanation:

since we have given that

cost of a new textbook = $85

according to question, the resale value of a textbook decreases by 25% with each previous owner,

so, our function becomes,

here, y is the total value of the text book after x owners.

hence, function will be

2/3=10/15

1/5=3/15

10+3=13/15

2 13/15 is the answer