Q: A bird is building a nest from twigs. The bird has put twelve twigs together already to make a circle. For each twig it placed into the circle, it wants to weave in six more twigs to fill out the nest. It knows a tree that has dropped a third of the twigs it needs. How many twigs will the bird still need to find to finish its nest?
A: The bird wants 12 * 6 = 72 twigs to add to the nest. It knows a tree that has dropped 72 * 1 / 3 = 24 twigs. Thus, the bird will still need 72 - 24 = 48 twigs to finish the nest. The answer is 48.

Q: Marcus takes a deck of standard playing cards and takes out all the face cards and the 8's. Mark picks a card at random and then replaces it 36 times. How many times should he expect to pick a card that's both red and has a number divisible by 3?
A: Without the face cards and the 8's, there are 9 cards of each suit. Half these cards are red, and 3 / 9 have numbers divisible by 3, so the odds of drawing a card divisible by 3 are 1 / 3. Multiply the odds of drawing a red card by the odds of drawing a card divisible by 3 to find the odds of both things happening: 1 / 3 * 1 / 2 = 1 / 6. Finally, multiplying the probability of drawing a red / 3 - divisible card by the number of cards Mark draws to find how many he should expect to meet his criteria: 1 / 6 * 36 cards = 6 cards. The answer is 6.

Q: One US cup equals 250ml. Brian is making lasagna for himself, his wife, his two kids, his parents, and his wife's parents. The recipe requires 1/2 a cup of milk per serving. How many 1L cartons of milk does Brian need to buy if each person is expected to eat 2 servings?
A:

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
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There will be a total of (1) Brian + (1) Brian's wife + (2) two kids + (2) Brian's parents + (2) Brian's in - laws = 1 + 1 + 2 + 2 + 2 = 8 people eating. If 1 person eats 2 serving of lasagna then 8 people will eat 8 * 2 = 16 servings. If each serving requires 1 / 2 cup of milk then 16 servings require 16 * 1 / 2 cups = 8 cups of milk. If one cup of milk equals 250 ml, then 8 cups of milk equal 8 * 250 = 2000 ml of milk. 1L carton of milk equals 1000ml of milk, therefore Brian needs 2000 / 1000 = 2 cartons of 1L milk. The answer is 2.