Examples with solutions for Volume of a Orthohedron: Finding Area based off Perimeter and Vice Versa

Exercise #1

Given the surface area of the cuboid equal to 94 cm.3

The length of the cuboid is 5 cm. and its width 4 cm.

Calculate the volume of the cube

555444

Video Solution

Step-by-Step Solution

To solve this problem, we are going to determine the volume of a cuboid given its length, width, and overall surface area. Here's how we will do it:

  • Firstly, calculate the height h h of the cuboid using the surface area formula.
  • Then, use the calculated height to determine the volume of the cuboid.

Now, let's work through each step:

Step 1: Calculate the height h h .

We know the surface area of a cuboid is given by the formula:

2(lw+lh+wh)=Surface Area 2(lw + lh + wh) = \text{Surface Area}

Substituting the known values:

2(54+5h+4h)=94 2(5 \cdot 4 + 5 \cdot h + 4 \cdot h) = 94

Simplify:

2(20+5h+4h)=94 2(20 + 5h + 4h) = 94 2(20+9h)=94 2(20 + 9h) = 94

Divide both sides by 2:

20+9h=47 20 + 9h = 47

Simplify further to solve for h h :

9h=27 9h = 27 h=3cm h = 3 \, \text{cm}

Step 2: Calculate the volume using the height h h .

Now that we know h=3cm h = 3 \, \text{cm} , use the volume formula for the cuboid:

Volume=l×w×h \text{Volume} = l \times w \times h Volume=5×4×3=60cm3 \text{Volume} = 5 \times 4 \times 3 = 60 \, \text{cm}^3

Therefore, the volume of the cuboid is 60cm3 \mathbf{60 \, \text{cm}^3} .

Answer

60 cm³

Exercise #2

Given the surface area of the cuboid equal to 136 cm3

Length of the cuboid is equal to 8 cm and the width is equal to half the length.

Calculate the volume of the cube

888

Video Solution

Step-by-Step Solution

To solve this problem, follow these steps:

  • Step 1: Identify the given information: l=8cm l = 8 \, \text{cm} , w=4cm w = 4 \, \text{cm} , and S=136cm2 S = 136 \, \text{cm}^2 .
  • Step 2: Use the surface area formula to find height h h : 136=2(84+8h+4h) 136 = 2(8 \cdot 4 + 8 \cdot h + 4 \cdot h) .
  • Step 3: Simplify and solve for h h .
  • Step 4: Use the volume formula V=lwh V = l \cdot w \cdot h .
  • Step 5: Substitute the value of h h into the volume formula.
  • Step 6: Calculate and obtain the final result.

Now, let's calculate:

Starting with the surface area equation:

136=2(84+8h+4h) 136 = 2(8 \cdot 4 + 8 \cdot h + 4 \cdot h) .

Simplifying gives:

136=2(32+8h+4h) 136 = 2(32 + 8h + 4h) .

136=2(32+12h) 136 = 2(32 + 12h) .

136=64+24h 136 = 64 + 24h .

Subtract 64 from both sides:

72=24h 72 = 24h .

Divide both sides by 24:

h=3cm h = 3 \, \text{cm} .

Now, calculate the volume using V=lwh V = l \cdot w \cdot h :

V=843 V = 8 \cdot 4 \cdot 3 .

V=96cm3 V = 96 \, \text{cm}^3 .

Therefore, the volume of the cuboid is 96cm3 96 \, \text{cm}^3 .

Answer

96 cm³

Exercise #3

The surface area of a rectangular prism 240 cm².

What is its volume according to the dimensions given in the diagram?

123

Video Solution

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Step 1: Identify the given information
  • Step 2: Apply the appropriate formula to find the unknown dimension
  • Step 3: Calculate the volume using the known dimensions

Now, let's work through each step:
Step 1: We know the surface area S=240cm2 S = 240 \, \text{cm}^2 , and two dimensions: 12 cm and 3 cm.

Step 2: The formula for the surface area of a rectangular prism is:
S=2(lw+lh+wh) S = 2(lw + lh + wh)
Substituting the known values into the equation:
240=2(12×3+12×h+3×h) 240 = 2(12 \times 3 + 12 \times h + 3 \times h)

Simplify and solve for h h :
240=2(36+12h+3h) 240 = 2(36 + 12h + 3h)
240=2(36+15h) 240 = 2(36 + 15h)
240=72+30h 240 = 72 + 30h
168=30h 168 = 30h
h=16830=5.6cm h = \frac{168}{30} = 5.6 \, \text{cm}

Step 3: Now that we know all dimensions, use the volume formula:
V=l×w×h=12×3×5.6 V = l \times w \times h = 12 \times 3 \times 5.6

Perform the calculation:
V=36×5.6=201.6cm3 V = 36 \times 5.6 = 201.6 \, \text{cm}^3

Therefore, the volume of the rectangular prism is 201.6cm3 201.6 \, \text{cm}^3 .

Answer

201.6cm3 201.6cm^3