It is known that the density of the object is 0.6 * 10 cubic kilogram per cubic meter, and the density of copper is 7.9 * 10 cubic kilogram per cubic meter. Then the object and copper are tied together and immersed in water. It is found that they are suspended in water

It is known that the density of the object is 0.6 * 10 cubic kilogram per cubic meter, and the density of copper is 7.9 * 10 cubic kilogram per cubic meter. Then the object and copper are tied together and immersed in water. It is found that they are suspended in water

The formula is: M + m / (P / M + P copper / M = 1.0 * 10 to the third power
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The carrying capacity of a cargo ship is 400t and its volume is 860m3. Now it has to load pig iron and cotton. The volume of pig iron is 0.3m3 per ton and that of cotton is 4m3 per ton. How many tons of pig iron and cotton can be loaded respectively to make full use of the carrying capacity and volume of the ship? (equation solution)

Suppose the pig iron is x tons,
The cotton is 400-x
0.3X+[400-X]*4=860
X=200
That is, pig iron is 200 tons, cotton is 200 tons

A ship has a capacity of 800 tons, a volume of 795 kg, a volume of 0.3 cubic meters per ton of pig iron, and a volume of 4 cubic meters per ton of cotton?
One yuan a time

Set: put x tons of iron, you can put (800-x) tons of cotton
Then 0.3x + 4 (800-x) = 795
X=650
650 tons of iron and 150 tons of cotton