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One kind of concrete is made of cement, sand and stone according to the standard of 2:3:5. Now there are 18 tons of cement, how many tons of sand and stone are needed?
The weight of each part: 18 △ 2 = 9 (tons); sand: 9 × 3 = 27 (tons); stone: 9 × 5 = 45 (tons). Answer: 27 tons of sand and 45 tons of stone are needed
One kind of concrete is made of cement, sand and stone according to the standard of 2:3:5. Now there are 18 tons of cement, how many tons of sand and stone are needed?
The weight of each part: 18 △ 2 = 9 (tons); sand: 9 × 3 = 27 (tons); stone: 9 × 5 = 45 (tons). Answer: 27 tons of sand and 45 tons of stone are needed
A kind of concrete is made of cement, sand and stone in the ratio of 2:3:5. How many tons of cement are needed to prepare 1920 tons of this kind of concrete?
2 + 3 + 5 = 10 (parts), 1920 × 210 = 384 (tons); answer: need 384 tons of cement
Concrete is made up of 3 parts of sand, 2 parts of stone and 1 part of cement. 2 tons of cement can mix () tons of concrete
Concrete is made up of 3 parts of sand, 2 parts of stone and 1 part of cement. 2 tons of cement can mix (12) tons of concrete
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- 1. A kind of concrete is made of cement, sand and stone in addition to water. The ratio of cement, sand and stone is 2:3:5 Sand 1800kg, stones 3520kg, the construction director asked the workers on the basis of not adding these three materials, as much as possible to mix this kind of concrete, so how many kg of this kind of concrete can be mixed with these materials at most?
- 2. Five tons of cement, yellow sand and stones are mixed into concrete with the ratio of cement, yellow sand and stones of 5:3:6. If the cement is just used up, will yellow sand and stones be enough? If not, how many tons less? If so, how many tons more?
- 3. A construction site uses 50m3 sand and gravel, and it is transported by trucks with a loading capacity of 3.5t. How many trucks should be transported at least? (the known density of sand is 2.6 × 103kg / m3)
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