Harry owns 3 geckos, 2 iguanas, and 4 snakes. If he spends $10 to feed each snake, $5 to feed each iguana, and $15 to feed each gecko every month, how much does he spend every year to feed all his pets? Give the rationale and then the answer.
Let's think step by step. He spends $10 / snake * 4 snakes = $40 to feed his snakes every month. He spends $5 / iguana * 2 iguanas = $10 to feed his iguanas every month. He spends $15 / gecko * 3 geckos = $45 to feed his geckos every month. So overall he spends $40 + $10 + $45 = $95 to feed all his pets every month. Therefore every year pet food costs him $95 / month * 12 months = $1140.. The answer is: 1140.

John decides to buy utensils. They come in 30 packs with an equal number of knives, forks, and spoons. How many packs does he need to buy if he wants 50 spoons? Give the rationale and then the answer.
Let's think step by step. Each pack contains 30 / 3 = 10 spoons. So he needs to buy 50 / 10 = 5 packs.. The answer is: 5.

A store decides to shut down and sell all of its inventory. They have 2000 different items which would normally retail for $50. They are offering an 80% discount and manage to sell 90% of the items. They owed $15000 to their creditors. How much money do they have left after the sale? Give the rationale and then the answer.
Let's think step by step. They sold 2000 * .9 = 1800 items. They offered a 50 * .8 = $40 discount. That means that each item sold for 50 - 40 = $10. So they made 1800 * 10 = $18,000. So they had 18,000 - 15,000 = $3,000 leftover.. The answer is: 3000.