Examples with solutions for Volume of a Orthohedron: Using ratios for calculation

Exercise #1

Shown below is a large cuboid composed of 4 smaller orthohedra equal in size.

AB=4 AB=4

BC=34AB BC=\frac{3}{4}AB

BE=12AB BE=\frac{1}{2}AB

Calculate the volume of the large cuboid.

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Video Solution

Step-by-Step Solution

To solve the problem, let's determine the dimensions of the large cuboid:

  • Step 1: Identify the given values: AB=4 AB = 4 , BC=34×AB BC = \frac{3}{4} \times AB , and BE=12×AB BE = \frac{1}{2} \times AB .
  • Step 2: Calculate the dimensions of the cuboid:
    • Since AB=4 AB = 4 , we find BC=34×4=3 BC = \frac{3}{4} \times 4 = 3 .
    • Next, BE=12×4=2 BE = \frac{1}{2} \times 4 = 2 .
  • Step 3: Calculate the volume of the large cuboid using the formula:
    • Volume=AB×BC×BE=4×3×2=24\text{Volume} = AB \times BC \times BE = 4 \times 3 \times 2 = 24.
    • Since the large cuboid is composed of four equal orthohedra, the volume of the entire large cuboid is 4×24=96cm3 4 \times 24 = 96 \, \text{cm}^3 .

So, the volume of the large cuboid is 96cm396 \, \text{cm}^3.

Answer

96 cm³

Exercise #2

A cuboid has a height of 4 cm.

The ratio between its length and its width is 3:2.

The volume of the cuboid is equal to 96 cm³.

Calculate the length of the cuboid.

444

Video Solution

Step-by-Step Solution

To solve this problem, we need to find the length of the cuboid using its volume and given dimensions. Let's break this down:

  • Step 1: Express the length and width using the ratio given. Let l=3x l = 3x and w=2x w = 2x , where x x is a common factor.
  • Step 2: Apply the formula for the volume of the cuboid, V=l×w×h V = l \times w \times h . Given that h=4 h = 4 cm and V=96 V = 96 cm³, the equation becomes:
96=(3x)×(2x)×4 96 = (3x) \times (2x) \times 4

Now, simplify and solve for x x :

96=24x2 96 = 24x^2

Dividing both sides by 24 gives:

x2=4 x^2 = 4

Taking the square root of both sides, we find:

x=2 x = 2

Thus, the length of the cuboid is:

l=3x=3×2=6 cm l = 3x = 3 \times 2 = 6 \text{ cm}

Therefore, the solution to the problem is 6 cm 6 \text{ cm} .

Answer

6 cm

Exercise #3

Given an cuboid whose length is equal to 3 cm width 2 cm and height 4 cm

Calculate the ratio between the volume of the orthocahedron and the area of the triangle ABK

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Video Solution

Step-by-Step Solution

To solve the problem, let's proceed with these steps:

  • Step 1: Calculate the volume of the cuboid.

  • Step 2: Determine the area of triangle ABK.

  • Step 3: Compute the ratio between the two quantities.

Now, let's execute these steps:
Step 1: The volume of the cuboid is given by the formula:

V=l×w×h V = l \times w \times h

Substituting the given dimensions:

V=3×2×4=24 cm3 V = 3 \times 2 \times 4 = 24 \text{ cm}^3

Step 2: To find the area of triangle ABK, we first need to determine its base and height. Given the dimensions, we consider segment AB as the height and segment BK as the base. Thus, base BK is the width, 2 cm, and height AB is the full height, 4 cm. The area is calculated by:

Area of ABK=12×base×height=12×2×4=4 cm2 \text{Area of } \triangle ABK = \frac{1}{2} \times \text{base} \times \text{height} = \frac{1}{2} \times 2 \times 4 = 4 \text{ cm}^2

Step 3: With these calculations, the ratio between the volume of the cuboid and the area of triangle ABK is:

Ratio=Volume of CuboidArea of ABK=244=6 \text{Ratio} = \frac{\text{Volume of Cuboid}}{\text{Area of } \triangle ABK} = \frac{24}{4} = 6

Therefore, the ratio between the volume of the orthocahedron and the area of triangle ABK is 6 6 .

Answer

6 6

Exercise #4

Given the cuboid whose volume 54Y cm3

The length of the cuboid is equal to Y cm

Its width is greater by 2 than the length of the cuboid.

The height of the cuboid is greater by 3 than its length.

Calculate the length of the cuboid (Y)

YYY

Video Solution

Answer

3 cm

Exercise #5

Given an cuboid whose length is equal to X

Its width is greater by 3 than its length.

The height of the cuboid is greater by 2 than its length

The volume of the cuboid is equal to 24X

Calculate the length of the cuboid

XXX

Video Solution

Answer

2 cm

Exercise #6

Given the cuboid whose length is equal to 3 cm

Width is equal to 2 cm

Height is equal to 4 cm

Calculate the ratio between the area of the right triangle and the volume of the cuboid.

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Video Solution

Answer

16 \frac{1}{6}