A practical problem of grade one in junior high school with a and B In 2007, a farmer contracted several mu of barren hills and invested 7800 yuan to plant 2000 fruit trees. This year, the total output of fruit is 18000 kg. The fruit is sold at a yuan per kilogram in the market and B yuan per kilogram in the orchard (B is less than a). The farmer brought the fruit to the market and sold 1000 kg per day on average, with the help of 8 people. Each person paid 25 yuan per day, and the agricultural vehicle freight and other taxes were 100 yuan per day (1) A and B represent the income from selling fruits in two ways respectively? (2) If a = 1.3 yuan, B = 1.1 yuan, and the two ways of selling fruits sell out all the fruits in the same time, please explain which way is better by calculation (3) The farmer strengthens the management of the orchard and strives to achieve a net income of 15000 yuan by next year. The farmer adopts the better selling method in (2). What is the growth rate of net income? (net income = total income total expenditure)

A practical problem of grade one in junior high school with a and B In 2007, a farmer contracted several mu of barren hills and invested 7800 yuan to plant 2000 fruit trees. This year, the total output of fruit is 18000 kg. The fruit is sold at a yuan per kilogram in the market and B yuan per kilogram in the orchard (B is less than a). The farmer brought the fruit to the market and sold 1000 kg per day on average, with the help of 8 people. Each person paid 25 yuan per day, and the agricultural vehicle freight and other taxes were 100 yuan per day (1) A and B represent the income from selling fruits in two ways respectively? (2) If a = 1.3 yuan, B = 1.1 yuan, and the two ways of selling fruits sell out all the fruits in the same time, please explain which way is better by calculation (3) The farmer strengthens the management of the orchard and strives to achieve a net income of 15000 yuan by next year. The farmer adopts the better selling method in (2). What is the growth rate of net income? (net income = total income total expenditure)

(1) 18000b-780018000a - (25 * 8 + 100) * 18000 / 1000-7800 (2) 18000b-7800 = 18000 * 1.1-7800 = 1200018000a - (25 * 8 + 100) * 18000 / 1000-7800 = 18000 * 1.3-5400-7800 = 10200 A: it's suitable to sell in orchard (3) (15000-12000) / 12000 = 25%