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There are 300 workers in the two workshops. Two fifths of the workers in workshop a are 55 more than one fourth of the workers in workshop B. how many workers are there in each workshop?
Suppose there are x people in solution a and 300-x people in solution B
2/5X-1/4（300-X）=55
13/20X-75=55
13/20X=130
X=200
300-X=300-200=100
Party A and Party B jointly produce a batch of parts, and what Party A produces is 53 times of that of Party B. If Party A gives Party B 55 parts, Party A produces 34 parts of Party B. how many parts did they produce?
Two teams of a and B dig a 300 meter long canal, two fifths of which are 55 meters more than one fourth of which are dug by B. how many meters are dug by each team?
Which boss is going to talk about More details
If team a digs x meters, team B digs (300-x) meters. According to the meaning of the question, the following equation is given: 2x / 5 = (300-x) / 4 + 55, x = 200, 300-x = 100, so team a digs 200 meters and team B digs 100 meters
The two construction teams dug a canal from both places at the same time. It is known that the first team dug two fifths of the canal, which was just connected with the second team. The second team dug the canal alone
The canal will take 15 days. After 6 days, the second team will be finished, and the first team will be finished. It will take several days
It takes 15 days for the second team to finish digging alone, so 15 / 5 = 3 (days). That is to say, the second team can dig 1 / 5 every three days, and the first team takes the same time to dig 2 / 5 as the second team, so the time for the first team to dig 2 / 5 is equal to 3 * 3 = 9 days. The first team digs 2 / 9 every day, the second team digs 2 / 5 after six days, and there is 3 / 5 left, so the first team needs 3 * 9 / 2 = 13.5 (days) to dig
Actually, it's very easy to draw a picture
The two construction teams dug a canal from both places at the same time. It is known that the first team dug two fifths of the canal, which was just connected with the second team. The second team dug the canal alone
Two construction teams excavate a canal from a and B at the same time. It is known that when the first team excavates 2 / 5 of the total length, it is just connected with the canal excavated by the second team. If the second team excavates the canal alone, it will take 15 days to complete. Now, after 6 days of excavation, the second team is transferred, and the rest of the work is completed by the first team. How many more days does the first team need to excavate? (the answer is 7.5 days.)
Suppose the total length of the canal is l, then the speed of the second team V2 = L / 15. According to the topic, the first team digs 2 / 5L = 0.4L, and the second team digs 3 / 5L = 0.6L, so the time of the two teams is the same. Therefore, 0.4l/v1 = 0.6l/v2v1 = 2 / 3 * V2 = 2L / 45. When the second team digs 6 days later, the remaining length L1 = L - (V1 + V2) * 6 = 1 /
Team a and team B build a canal together. Team a planned to build two fifths of the total length of the canal. In actual work, after completing the planned task, team a built an additional 0.4 km. After the canal is repaired, the actual length ratio of team a and team B is 4:5. How long is the canal?
The length of the canal is x km
Because we plan to repair 2 / 5 of a, so we plan to repair 3 / 5 of B
Now if a repairs 0.4km more, then B repairs 0.4km less
The equation is listed according to the equivalence relation
(2/5 x +0.4)/ (3/5x -0.4)=4/5
(2/5 x +0.4)= 4/5(3/5x -0.4)
2/5x +0.4 =12/25 x- 8/25
0.4+8/25 =12/25 x -2/5 x
10/25 +8/25=2/25 x
2/25x=18/25
x=18/25 ×25/2
x=9
After testing, x = 9 is the solution of the original equation (fractional equation to test Oh)
A: the canal is 9 km long
There are 140 tons of coal in pile a and pile B. when pile a transports 14 tons and pile B transports 10 tons, the tonnage ratio of pile a and pile B is 6:5. How many tons of coal are there in each pile?
Suppose there are x tons of coal in pile a and 140-x tons of coal in pile B. from the meaning of the title, we can get: (1-14) x: (140-x-10) = 6:5, & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; 34x: (130-x) = 6:5, & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp
There are two piles of coal, i.e. pile a and pile B. If 27 coal is transported from pile B to pile a, the weight of the two piles of coal is equal. The original pile B has more coal than pile a ()
A. 27B. 43C. 47D. 34
According to the meaning of the title, if the weight of pile B is "1", then the weight of pile a is: (1-27) - 27 = 57 − 27 = 37, so the original pile B coal is more than pile a coal: (1-37) △ 37 = 47 △ 37 = 43
A business company has two warehouses to store color TV sets. The storage ratio of warehouse A and warehouse B is 7:3. If 30 TV sets are transferred from warehouse A to warehouse B, the ratio of warehouse A and warehouse B is 3:2. How many TV sets are stored in these two warehouses?
A: originally 73 + 7 = 710, later 33 + 2 = 35, 30 ^ (710 − 35), = 30 ^ (110, = 300 sets); a: these two warehouses used to store 300 sets of TV sets
Xiao Ming's family moved to a new house and wanted to buy a new refrigerator. Xiao Ming and his mother took a fancy to a and B refrigerators in the mall. Among them, the price of a refrigerator is 2100 yuan, and the daily power consumption is 1 degree; B refrigerator is an energy-saving new product, the price is 2220 yuan, and the daily power consumption is 0.5 degree, and the effect of the two refrigerators is the same, Please calculate and explain the price. It's more cost-effective to buy Refrigerator a when it's at least a discount? (0.5 yuan per kilowatt hour. The service life of both refrigerators is 10 years, with an average of 300 days per year.)
Solve by equation
Daily electricity consumption of refrigerator B: 0.5 times 0.5 = 0.25 (yuan)
10 years: 0.25 times 300 times 10 = 750 yuan
Daily electricity consumption of refrigerator a: 1 times 0.5 = 0.5 yuan
10 years: 0.5 times 300 times 10 = 1500 yuan
Price of refrigerator B: 750 yuan + 2220 yuan = 2970 yuan
I have a discount of X
2100X+1500=2970
2100X=1470
X = 1470 divided by 2100
X=0.7
So a 7% discount on refrigerator a is equal to the cost of refrigerator B
So it's worth less than 70% off
I'll give you some hard work for typing so many words
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