A rancher owns a mixture of 8 sheep and 5 cattle that graze on his land. In a typical year, the rancher will allow his animals to feed off his pastures for as long as possible before they run out of grass. After the pastures run out of grass, he must buy feed corn for $10 per bag. Each cow eats 2 acres of grass per month, and each sheep eats 1 acre of grass per month. Additionally, a bag of feed corn can feed each cow for 1 month and each sheep for 2 months.  If the rancher's pasture contains 144 acres of grass, how much will the rancher need to spend on feed corn to feed his animals each year?
Let's think: First, the 144 acres of grass will be eaten according to the equation 5 * 2 * T + 8 * 1 * T = 144. Solving this equation for T, we find 18 * T = 144, or T = 8 months of food are covered by the animals grazing on the rancher's pasture. This means the farmer must buy feed corn for the remaining 12 - 8 = 4 months. Next, the rancher's 8 sheep will require 4 / 2 = 2 bags of feed corn each, or 8 * 2 = 16 bags of feed corn in total for the 4 month period. The rancher's 5 cows will require 4 / 1 = 4 bags of feed corn each, or 5 * 4 = 20 bags of feed corn in total for the month. Therefore, the rancher needs 16 + 20 = 36 bags of feed corn for all of his animals. So, the rancher will need to spend 36 * 10 = $360 per year on feed corn.. The answer is: 360.

Gretchen draws caricatures in the park on the weekends. She charges $20.00 per drawing. If she sold 24 on Saturday and 16 on Sunday, how much money did she make?
Let's think: She drew 24 on Saturday and 16 on Sunday for a total of 24 + 16 = 40 drawings. She charges $20.00 per drawing and she drew 40 caricatures so she made $20 * 40 = $800.. The answer is: 800.

James collects all the fruits from his 2 trees. Each tree has 20 plants. Each plant has 1 seed and he plants 60% of those. How many trees did he plant?
Let's think: He got 20 * 2 = 40 seeds. That means he plants 40 * .6 = 24 trees.. The answer is: 24.

Lizzy's mother gave her 80 cents and her father gave her 40 cents for keeping to her promise. She went to her uncle's and spent 50 cents buying candy for her little cousin. Her uncle gave her another 70 cents. How many cents does she have now?
Let's think:
She got 80 + 40 = 120 cents from her mother and father. She spent 50 cents on candy leaving 120 - 50 = 70 cents. Her uncle gave her an additional 70 cents for a total of 70 + 70 = 140 cents.. The answer is: 140.