Question

Помогите..масса 4/5 кубических дм сосны равна 2/5 кг. какова масса 1 кубического дм сосны? Каков объём соснового бруска массой 1 кг?

Answer 1

4/5 дм3=2/5 кг
1 дм3= х кг

х=$\frac{1* \frac{2}{5} }{ \frac{4}{5} } = \frac{2}{5}: \frac{4}{5}= \frac{2}{5}* \frac{5}{4}= \frac{2}{4}= \frac{1}{2}$кг - 0,5 кг весит 1 дм3 сосны

формула объема V=$\frac{m}{p}$, где р-плотность, m - масса, плотность сосны 520 кг/м3
соответственно V=0.002 m3

Answer 2

Calculation of the Mass of 1 Cubic Decimeter of Pine

To find the mass of 1 cubic decimeter (dm³) of pine, we can use the given information that the mass of 4/5 cubic dm of pine is 2/5 kg.

Let's denote the mass of 1 cubic dm of pine as "m" (in kg).

According to the given information, we have the following equation:

(4/5) dm³ of pine = (2/5) kg

To find the mass of 1 cubic dm of pine, we can set up a proportion:

(4/5) dm³ / (2/5) kg = 1 dm³ / m kg

Simplifying the proportion, we get:

(4/5) / (2/5) = 1 / m

Cross-multiplying, we have:

(4/5) * m = (2/5) * 1

Simplifying further, we get:

4m/5 = 2/5

Cross-multiplying again, we have:

4m = 2

Dividing both sides by 4, we find:

m = 2/4

Simplifying the fraction, we get:

m = 1/2

Therefore, the mass of 1 cubic dm of pine is 1/2 kg.

Calculation of the Volume of a Pine Beam with a Mass of 1 kg

To find the volume of a pine beam with a mass of 1 kg, we need to use the density of pine.

Unfortunately, the given information does not provide the density of pine, which is necessary to calculate the volume.

Please provide the density of pine so that we can proceed with the calculation.