PLS PLS PLS HELP NO LINKS, NO STEALING POINTS, AND ONLY CORRECT ANSWERS OR YOU WILL BE REPORTED IM GIVING BRAINLIEST

Hi, can anyone show me how to do this problem? 100 points for this. in advance

Organic apples are on special for $1.50 per pound. does total cost vary inversely or directly with the number of pounds purchased? find the cost of 3.4 pounds of apples. a. inversely: $5.10 b. directly; $5.10 c. inversely: $2.27 d. directly; $2.27

Collin did the work to see if 10 is a solution to the equation r/4=2.4