In the school's library, there are 2300 different books. 80% of all the books are in English, but only 60% of these books were published in the country. How many English-language books have been published outside the country? Give the rationale and then the answer.
Let's think step by step. There are 80 / 100 * 2300 = 1840 books in English at the library. Out of these books, only 60 / 100 * 1840 = 1104 were published inside the country. So there are 1840 - 1104 = 736 books in English published outside of the country.. The answer is: 736.

Mr. Jesiah is a dairy cow farmer with cows producing 200 gallons of milk every day. The expenses for maintenance of the dairy farm and purchase of feeds is $3000 per month. Calculate his total income in June if he sells 1 gallon of milk at $3.55. Give the rationale and then the answer.
Let's think step by step. In a day, Mr. Jesiah's total income from the sale of the milk is $3.55 / gallon * 200 gallons / day = $710 / day. In June, his total income is $710 / day * 30 days = $21300. The net income from the sale is $21300 - $3000 = $18300.. The answer is: 18300.

Cindy can jump rope for 12 minutes before tripping up on the ropes. Betsy can jump rope half as long as Cindy before tripping up, while Tina can jump three times as long as Betsy. How many more minutes can Tina jump rope than Cindy? Give the rationale and then the answer.
Let's think step by step. Betsy jumps half as long as Cindy, who jumps for 12 minutes so Betsy jumps 12 / 2 = 6 minutes. Tina jumps three times as long as Betsy, who jumps for 6 minutes so Tina jumps 3 * 6 = 18 minutes. Tina can jump for 18 minutes and Cindy and jump for 12 minutes so Tina can jump 18 - 12 = 6 minutes longer.. The answer is: 6.