Billy is counting the rings in two trees. Weather fluctuations in this area mean that each tree's rings are in groups of two fat rings and four thin rings. If Billy counts 70 ring groups in the first tree and 40 ring groups in the second tree, how much older is the first tree? (Trees grow 1 ring per year.) Give the rationale and then the answer.
Let's think step by step. First find the total number of rings in a ring group: 2 rings + 4 rings = 6 rings. Then subtract the number of ring groups in the second tree from the number in the first tree to find the difference: 70 groups - 40 groups = 30 groups. Then multiply that number by the number of rings in a group to find the difference in the trees' ages: 30 groups * 6 rings / group = 180 rings, or 180 years.. The answer is: 180.

Mary had 6 lambs and 2 of the lambs had 2 babies each. She traded 3 lambs for one goat. One morning, she woke up and found an extra 7 lambs in the field. How many lambs does Mary have? Give the rationale and then the answer.
Let's think step by step. 2 of her lambs had 2 babies each so that adds 2 * 2 = 4 lambs. She starts with 6 and adds 4 baby lambs so she had 6 + 4 = 10 lambs. She traded 3 of those lambs for a goat so she has 10 - 3 = 7 lambs. She has 7 and woke up to find 7 more lambs in the field so she has a total of 7 + 7 = 14 lambs.. The answer is: 14.

The recipe for a four-person cake requires 2 eggs and 4 cups of milk. Tyler wants to use this recipe to make a cake for eight people. If Tyler has 3 eggs in the fridge, how many more eggs does Tyler need to buy? Give the rationale and then the answer.
Let's think step by step. A cake for eight people would require 8 / 4 = 2 times as many eggs as a 4 people cake. If a 4 - person cake requires 2 eggs, then an 8 - person cake requires 2 x 2 = 4 eggs. Tyler needs to buy 4 - 3 = 1 more egg.. The answer is: 1.