Surface Area of a Cuboid Practice Problems & Solutions

Master surface area of cuboid calculations with step-by-step practice problems. Learn formulas, solve real-world applications, and boost your geometry skills today.

📚What You'll Master in This Practice Session
  • Apply the surface area formula SA = 2(lw + lh + wh) to rectangular prisms
  • Calculate surface area using length, width, and height measurements accurately
  • Solve real-world problems involving boxes, containers, and packaging materials
  • Convert between different units of measurement in surface area calculations
  • Identify and correct common mistakes in cuboid surface area problems
  • Build confidence with progressively challenging surface area word problems

Understanding Surface Area of a Cuboid

Complete explanation with examples

Rectangular Prisms are made up of 6 6 different rectangles. When faced with an exercise or exam that asks you to calculate the surface area of a rectangular Prism, use the formula below.

The formula: how to calculate the area of a rectangular prism (rectangular orthohedron)?

S=2×(Width×Length+Height×Width+Height×Length) S=2 \times (Width \times Length+ Height \times Width + Height\times Length)

S= surface area

how to calculate the area of a rectangular prism (rectangular orthohedron)

Detailed explanation

Practice Surface Area of a Cuboid

Test your knowledge with 19 quizzes

The surface area of the cuboid shown below is 147 cm².

What are the dimensions of the cuboid that are not labelled in the drawing?

171717

Examples with solutions for Surface Area of a Cuboid

Step-by-step solutions included
Exercise #1

Look at the cuboid below.

What is its surface area?

333333111111

Step-by-Step Solution

We identified that the faces are

3*3, 3*11, 11*3
As the opposite faces of an cuboid are equal, we know that for each face we find there is another face, therefore:

3*3, 3*11, 11*3

or

(3*3, 3*11, 11*3 ) *2

To find the surface area, we will have to add up all these areas, therefore:

(3*3+3*11+11*3 )*2

And this is actually the formula for the surface area!

We calculate:

(9+33+33)*2

(75)*2

150

Answer:

150

Video Solution
Exercise #2

Calculate the surface area of the orthohedron below using the data in the diagram.

333555222

Step-by-Step Solution

To solve this problem, we'll utilize the formula for the surface area of a cuboid. The steps are as follows:

  • Step 1: Identify the dimensions from the problem. The dimensions provided are a=3a = 3, b=5b = 5, and c=2c = 2.
  • Step 2: Apply the surface area formula for a cuboid. The formula is: 2(ab+bc+ac) 2(ab + bc + ac) where aa, bb, and cc are the dimensions of the cuboid.
  • Step 3: Substitute the known values into the formula: 2(35+52+32) 2(3 \cdot 5 + 5 \cdot 2 + 3 \cdot 2)
  • Step 4: Calculate each term inside the parentheses: - ab=35=15 a \cdot b = 3 \cdot 5 = 15 - bc=52=10 b \cdot c = 5 \cdot 2 = 10 - ac=32=6 a \cdot c = 3 \cdot 2 = 6
  • Step 5: Sum the results from Step 4: 15+10+6=31 15 + 10 + 6 = 31
  • Step 6: Multiply the sum by 2 to find the total surface area: 2×31=62 2 \times 31 = 62

Thus, after performing the necessary calculations, the surface area of the orthohedron is 62 62 square units.

Answer:

62

Video Solution
Exercise #3

Look at the the cuboid below.

What is its surface area?

333555888

Step-by-Step Solution

First, we recall the formula for the surface area of a cuboid:

(width*length + height*width + height*length) *2

As in the cuboid the opposite faces are equal to each other, the given data is sufficient to arrive at a solution.

We replace the data in the formula:

(8*5+3*5+8*3) *2 =

(40+15+24) *2 =

79*2 =

158

Answer:

158

Video Solution
Exercise #4

Look at the cuboid below.

888555121212

What is the surface area of the cuboid?

Step-by-Step Solution

Let's see what rectangles we have:

8*5

8*12

5*12

Let's review the formula for the surface area of a rectangular prism:

(length X width + length X height + width X height) * 2

Now let's substitute all this into the exercise:

(8*5+12*8+12*5)*2=
(40+96+60)*2=
196*2= 392

This is the solution!

Answer:

392 cm²

Video Solution
Exercise #5

What is the surface area of the cuboid in the figure?

141414171717727272

Step-by-Step Solution

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

  • Step 1: Identify the dimensions of the cuboid.
  • Step 2: Apply the surface area formula for a cuboid.
  • Step 3: Calculate and interpret the result.

Now, let’s work through each step:

Step 1: We have the dimensions as follows:
- Length (ll) = 72
- Width (ww) = 17
- Height (hh) = 14

Step 2: Apply the surface area formula:
The total surface area AA is calculated using the formula:
A=2(lw+lh+wh) A = 2(lw + lh + wh) Substitute the given dimensions into the formula:
A=2((72×17)+(72×14)+(17×14)) A = 2((72 \times 17) + (72 \times 14) + (17 \times 14))

Step 3: Calculate each multiplication and sum them up:
- Calculate 72×17=122472 \times 17 = 1224
- Calculate 72×14=100872 \times 14 = 1008
- Calculate 17×14=23817 \times 14 = 238
Now substitute back into the equation:
A=2(1224+1008+238) A = 2(1224 + 1008 + 238) Add the products:
A=2(2470) A = 2(2470) Finally, multiply by 2:
A=4940 A = 4940

Therefore, the surface area of the cuboid is 4940square units 4940 \, \text{square units} .

Answer:

4940

Video Solution

Frequently Asked Questions

What is the surface area of a cuboid formula?

+
The surface area of a cuboid formula is SA = 2(lw + lh + wh), where l is length, w is width, and h is height. This formula calculates the total area of all six rectangular faces of the cuboid.

How do you find surface area of a cuboid step by step?

+
To find surface area of a cuboid: 1) Identify length, width, and height. 2) Calculate lw, lh, and wh. 3) Add these three products together. 4) Multiply the sum by 2 to get total surface area.

What's the difference between surface area and volume of a cuboid?

+
Surface area measures the total area of all outer faces (measured in square units), while volume measures the space inside the cuboid (measured in cubic units). Surface area uses SA = 2(lw + lh + wh), volume uses V = lwh.

How to calculate surface area of cuboid in cm²?

+
Ensure all measurements are in centimeters first. Then apply the formula SA = 2(lw + lh + wh). The result will automatically be in cm² since you're multiplying cm × cm for each face area.

What are common mistakes when finding cuboid surface area?

+
Common mistakes include: • Forgetting to multiply by 2 • Using volume formula instead • Mixed units without conversion • Calculating only some faces • Confusing length, width, and height positions

When do we use surface area of cuboid in real life?

+
Surface area of cuboids is used for: painting walls and ceilings, wrapping gifts, calculating material needed for boxes, determining fabric for furniture covers, and estimating wallpaper or tile requirements.

How do you solve cuboid surface area word problems?

+
For word problems: 1) Read carefully to identify length, width, height. 2) Write down what you're looking for. 3) Apply SA = 2(lw + lh + wh). 4) Include proper units in your answer. 5) Check if answer makes sense in context.

Can surface area of a cuboid be negative?

+
No, surface area cannot be negative since it represents physical area measurement. If you get a negative result, check your calculations and ensure all length, width, and height values are positive numbers.

More Surface Area of a Cuboid Questions

Continue Your Math Journey

Topics Learned in Later Sections

Practice by Question Type