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There is a desert where a car travels 200 kilometers every day, and each car can only be fully loaded with gasoline for 24 days. One day, a and B cars eat from place a at the same time. It is stipulated that no matter how far they drive, they must return to place a along the original road. In order to make car a drive as far as possible, after driving for a certain distance, car B only leaves the gasoline for himself to return to place a, and supplies the remaining gasoline to car a, What is the longest distance a car can drive? ------------------------------------------------------- One day a and B cars start from a at the same time! (I have the wrong number) Can you make an equation?
Suppose that the longest distance of car a is x km, and car B starts to return after driving with car a for y days
X/200=24+Y
Y+Y+Y=24
solve equations:
X=6400
Y=8
The train of thought is as follows
First equation:
The number of days that car a can go is equal to the number of days that car B contributes gasoline plus the number of days that car a can go
Second equation:
The number of days that car B accompanies car a is equal to the number of days that car B needs to return and the number of days that car B contributes gasoline to car A. It can only carry gasoline for 24 days in total
The problem is this:
There are 200t chemical fertilizer in city a and 300t chemical fertilizer in city B. now we need to transport chemical fertilizer to C and D. if the freight from city a to C and D is 20 yuan / T and 25 yuan / T respectively, and the freight from city B to C and D is 15 yuan / T and 22 yuan / T respectively, it is known that C needs 220t and D needs 280t. If an individual household has contracted this transportation task, please help him calculate, how to adjust the freight at least?
There are no answers to the exercises in the unit. If the teacher doesn't talk about such problems, is there a better way to solve them?
Find the problem solving of that unit!
It's not something good students do. I just look at it once in a while
(people teach mathematics)
_______________________
I remember some of this question. Isn't it from the book? I'm wrong
I can't help it. I didn't learn it well
I'm afraid I'll get the monthly exam. What should I do
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