Three people went backpacking in Yosemite National Park. On the first and second days, each hiker had a serving of food for breakfast, lunch and dinner.
A large noisy, brown bear barged into camp the second night, got the food down from
the tree where they had hung it, and ate one half the food of the food that was left. The
next morning, after they all had breakfast, they found they had 4 servings left. They
decided to hike back to the car. How many servings of food did they begin the trip with?