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When I solve the applied problems of mathematical engineering problems, I know the equivalent relation, but I can't make equations. What should I do?
There is a big difference between solving practical problems with equations and using arithmetic. The key to solving practical problems with equations is to find out the equivalent relationship between various quantities (whether known or unknown), list the relationship and form the equation, and then substitute the known number into the equation, and use letters (such as x) to replace the unknown number
A mathematical problem in Engineering
For a project, it takes 30 days for Party A to complete the task alone, while it takes 20 days for Party B to complete the task alone. Now Party A has done it for several days, and Party B has taken over. In this way, it took 22 days for them to complete the task. How many days has party a done it?
Set up a total of X days
x/30+(22-x)/20=1
2x+66-3x=60
x=6
A did it for six days
There is a mathematical problem about engineering problems to ask you!
It takes 6 hours for two people to work together to process a batch of parts. If it takes 15 hours for one person to work alone, how long does it take for the other person?
There is another question!
For a section of road, one fourth of the total length is traveled in the first hour, and 75 km is traveled in the second hour. At this time, the ratio of the distance traveled to the rest is 2:3. How many km is the total length of this section of road?
1. It takes 6 hours for two people to cooperate, so they can complete 1 / 6 in 1 hour, one of them can complete 1 / 15 in 1 hour alone, and the other can complete 1 / 6-1 / 15 in 1 hour alone = 1 / 10, so it takes 10 hours for the other to complete it alone
The first line is 2 / 4 of an hour
2/5-1/4=3/20
75 / (3 / 20) = 500 (km)
The journey is 500 kilometers long
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