Question: Cary is an engineer in charge of designing an irrigation system for three farmers. Farmer Bob grows 3 acres of corn, 9 acres of cotton, and 12 acres of beans. Farmer Brenda grows 6 acres of corn, 7 acres of cotton, and 14 acres of beans. Farmer Bernie grows 2 acres of corn and 12 acres of cotton. If corn takes 20 gallons of water an acre, cotton takes 80 gallons of water an acre, and beans take twice as much water as corn, what percentage of the total water used will go to Farmer Bob's farm?
Answer: First figure out how much water beans take by multiplying the water use for corn by 2: 20 gallons / acre * 2 = 40 gallons / acre. Next, calculate Bob's water use by multiplying each plant's water use per acre by the number of acres he planted, then adding up the total water use for all three crops: 3 * 20 + 9 * 80 + 12 * 40 = 1260. Now do the same thing for Brenda: 6 * 20 + 7 * 80 + 14 * 40 = 1240. And do the same thing for Bernie: 2 * 20 + 12 * 80 = 1000. Now add up each farmer's water use to find the total water use: 1260 + 1240 + 1000 = 3500. Now divide Bob's water use by the total water use and multiply by 100 to find what percentage of the water he used: 1260 / 3500 * 100 = 36%. The answer is 36.

Question: James and Ali together own $250. If you know that James owns $40 more than Ali, then calculate the amount owned by James.
Answer: Let X be the amount owned by James. The amount owned by Ali is X - $40. The total amount owned by both of them X + (X - $40) = $250. Combining like terms, we get X * 2 - $40 = $250. Adding $40 to both sides, we get X * 2 = $290. Dividing both sides by 2, we get X = $145. The answer is 145.

Question: John runs a telethon to raise money. For the first 12 hours, he generates $5000 per hour. The remaining 14 hours, he generates 20% more per hour. How much total money does he make?
Answer: He gets 12 * 5000 = $60000 for the first 12 hours. For the next 14 hours, he gets 5000 * .2 = $1000 more per hour. So he gets 5000 + 1000 = $6000 per hour. So he gets 6000 * 14 = $84000. So in total, he makes 84000 + 60000 = $144,000. The answer is 144000.

Question: John can read a book 60% faster than his brother. If his brother takes 8 hours to read a book, how long would it take John to read 3 books?
Answer:

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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Reading 60% faster means John's brother takes 1 + .6 = 1.6 times as long as John to read. So John reads a book in 8 / 1.6 = 5 hours. So it would take John 5 * 3 = 15 hours to read 3 books. The answer is 15.