Math Equation Problem in the Sixth Grade of Primary School 100 (There must be a process and an answer)
1. A ship carries 595 tons of oil and B ship carries 225 tons of oil. How many tons of oil must be pumped from ship B to ship A to make the oil load of ship A reach four times that of ship B? Assuming that X tons of oil is pumped from ship B, then 595+x = (225-x) × 4 595+x = 900-4x4x+x = 900-595 5x = 305x = 6 1 a: 61ton of oil must be pumped from ship B to ship A. After 30 minutes, A returned to Xizhen for official business, stayed in Xizhen for half an hour, and then went to Dongzhen. The result is 30 minutes later than B, trying to find the distance between the two towns. Solution: Suppose it takes X hours for A to set off from Xizhen to Dongzhen for the second time. Then15x =10x (0.5x3)+10 (x-0.5)15x =15+10x-515x. Answer =30: The distance between the two towns is 30 kilometers. My brother is three times as old as his brother. My brother is the same age as his brother. Brother and brother are 30 years old. How old are they now? Solution: Let my brother's age be X, then multiply both sides of the equation by 3 to get 6x-90 = 90-3x-6x+4x = 90+9010x =180x =18 and substitute 30-x = 30-18. My brother is now 12 years old. Xiaohong, Xiao Li and Xiao Qiang each bought some exercise books with the same amount of money. Xiaohong bought 0.6 yuan, two less than Xiao Qiang, and Xiao Li bought 0.4 yuan, three more than Xiao Qiang. How many exercise books did Xiao Qiang buy? What is the price of each book? Answer: Suppose Xiao Qiang bought X exercise books. Then 0.6× (x-2) = 0.4× (x+3) 0.6x-1.2 = 0.4x+1.20.6x =1.2+1.20.2x = 0.5 Answer: Xiao Qiang bought 12 exercise books, each in 0.5 yuan. There are several bags of rice in the grain depot. More than half of the stored rice was shipped out for the first time, and the remaining half was shipped out for the second time in 10 bags. The third time, 200 bags were brought in, and there were 260 bags left in the grain depot. How many bags of rice are there? Solution: If the original rice X package is set in the grain depot, then x=240 A: the original rice in the grain depot is 240 packages. 6. Li Gang rides a bike from place A to place B, first riding an uphill road and then riding a flat road. After he arrived in B, he immediately returned to A, and it took him three hours to go back and forth. Li Gang rode six kilometers more on the flat road than on the uphill road and three kilometers more on the downhill road than on the flat road. It is known that he rode five kilometers less in the first hour than in the second hour (he rode an uphill road and a flat road in the second hour), and three kilometers less in the second hour than in the third hour. So: (1) How many minutes did Li Gang spend on the uphill road? (2) How many minutes did it take to go down the mountain? (3) How many kilometers is the distance between Party A and Party B? Solution: (1) Because the uphill road is less than 6 kilometers per hour, and the first hour is less than the second hour, the uphill road takes * * * time: (2) Suppose the third hour is x hours for the paved road and 1-x hours for the downhill road. So 6x+(6+3) (1-x) = 86x+9 (1-x) = 86x+9-9x = 89-3x = 83x = 9-8, so downhill * * is 60-20=40 (minutes So: If both sides of the equation are multiplied by 6, then 7x = 4 (x+9) 7x = 4x+363x = 36x =12 (hour) (kilometer answer: 70 minutes uphill, 40 minutes downhill, and the distance between Party A and Party B is 24.5 kilometers. )