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In the third quarter of last year, an engineering team undertook the glorious task of laying a section of 3 km long subway track. After laying 600 meters, the engineering team improved its technology and laid 10 meters more every day than before. As a result, it took 80 days to complete the task How many meters of track are laid every day after technology?
Suppose that the engineering team lays x meters of track every day after improving the technology, then it lays (X-10) meters of track every day before improving the technology. According to the theme, it gets 600X − 10 + 3000 − 600X = 80, 2x2-95x + 600 = 0, and the solution is X1 = 40, X2 = 7.5. It is tested that X1 = 40, X2 = 7.5 are the roots of the original equation, but x2 = 7.5 is not in line with the actual significance, so we can omit ∧ x = 40, answer: the engineering team lays 40 meters of track every day after improving the technology Rice
According to statistics, from October 11, 2008 to February 28, 2009, the average daily passenger traffic volume of ground bus and rail transit is 16.96 million person times, and the average daily passenger traffic volume of ground bus is 690000 person times less than 4 times of the average daily passenger traffic volume of rail transit During this period, the average daily passenger traffic volume of ground bus and rail transit are respectively tens of thousands of people?
Suppose the average daily passenger volume of rail transit is x 10000 person times, and that of ground bus is y 10000 person times. According to the meaning of the question: x + y = 1696y = 4x − 69 solution: x = 353y = 1343 answer: the average daily passenger volume of rail transit is 3.53 million person times, and that of ground bus is 13.43 million person times
According to the different values of M, we discuss the solution set of the inequality mx-2m greater than x-3
mx-2m>x-3
(m-1)x>2m-3
if m>1,x>(2m-3)/(m-1)
m
If the solution set of the inequality MX-3 is greater than 2x + m and X is less than m + 3 / m-2, then the value range of real number m is analytic, detailed and clear
m2x+m
∴（m-2）x＞m＋3
The solution set is x less than m + 3 / m-2
∴m-2＜0
∴m＜2
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