Chapter 9.4, Problem 28P

Jane had a bottle filled with juice. At first, she drank $\frac{1}{5}$ of the juice In the bottle. After 1 hour, she drank $\frac{1}{4}$ of the juice remaining in the bottle. After another 2 hours, she drank $\frac{1}{3}$ of the remaining juice in the bottle. At that point, Jane checked how Much juice was left in the bottle: There was $\frac{2}{3}$ of a cup left. No other juice was added to or removed from the bottle. How much juice was in the botte originally? Solve this problem, and explain your solution.