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Volume x density = weight, what is the density?
1、 The "density" of physics represents a property of matter
For the same substance, the ratio of mass to volume is the same;
The ratio of mass to volume is generally different for different substances
2、 Definition of "density" in Physics:
The mass per unit volume of a substance is called its density
3、 Symbol: ρ
4、 Formula: ρ = m / V
5、 Setting:
1. Main unit: kg / M
2. Unit 1: g / cm
3. Conversion relation: 1g / cm = 10 kg / M
12 tons of cement, yellow sand and stones are transported from the construction site, and they are made into concrete according to the ratio of 5:3:2. If the cement is just used up, what will happen to yellow sand?
12 tons of cement, yellow sand and stones are transported from the construction site, and they are made into concrete according to the ratio of 5:3:2. If the cement is just used up, what will happen to the yellow sand? I need to help quickly
5+3+2 = 10
12 - 12÷5/10×3/10
= 12 - 24×3/10
= 12 - 7.2
=4.8 tons
A: 4.8 tons of Huangsha will remain
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