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Three math problems, how many can be solved 1. The total weight of the two barrels of oil a and B is 60 kg. The weight ratio of the remaining oil and B is 3:7. How many kg of oil was there in barrel a? 2. To process a batch of parts, the time ratio of a, B and C is 3:4:5? 3. There are three granaries a, B and C, with a total grain weight of 96 tons. If 3 tons are transported from each of the two granaries AB to C, the grain storage ratio of the three granaries is 4:3:1. How many tons of grain were stored in each of the three granaries
1. Suppose that barrel a used to have x kg oil and barrel B used to have y kg oil
x+y=60
(x-10)÷y=3/7
The solution is x = 25, y = 35
2. Because the time ratio of a, B and C is 3:4:5, the quantity ratio of a, B and C per hour is 20:15:12
Because three people are required to complete the task in the same time, each of them should process 400300240 pieces
3. Let K 4K + 3K + k = 96, k = 12
At present, a granary is 48 tons, B granary is 36 tons, C granary is 12 tons
Then the original grain warehouse A is 51 tons, the grain warehouse B is 39 tons, and the grain warehouse C is 6 tons
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