Confused on this one help me solve for point B

Adam drew two same size rectangles and divided them into the same number of equal parts. he shaded 1/3 of one rectangle and 1/4 of the other rectangle. what is the least number of parts into which both rectangles could be divided into?

Jackie purchased 3 bottles of water and 2 cups of coffee for a family for $7.35. brian bought 4 bottles of water and 1 cup of coffee for his family for $7.15. how much does each bottle of water cost? how much does each cup of coffee cost? i need this done

Which one ? is the answer and how to find this answer