Question: You have a flashlight that takes 2 working batteries. You have 8 batteries but only 4 of them work.
What is the fewest number of pairs you need to test to guarantee you can get the flashlight on?
Answer: 7. If you break the batteries into 3 groups: Two groups of 3 and one group of 2. By doing this you guarantee that one of the groups has 2 working batteries. Both of the groups of 3 have 3 possible combinations of 2 batteries and the group of 2 only has 1 combination. So, 3 + 3 + 1 = 7 tries at most to find two working batteries.
Question: What do you get when you cross a cheetah and a burger?
Answer: Fast food.
Question: What tastes better than it smells?
Answer: A tongue.
Question: What goes in the water black and comes out red?
Answer: A lobster.
Question: What loses its head in the morning and gets it back at night?
Answer: A pillow.
Question: What two things can you never eat for breakfast?
Answer: Lunch and dinner!