Look at the orthohedron shown in the figure below.
Side b is 20% longer than side a.
Side c is 20% longer than side b.
Calculate a, c, and b given that the surface area of the orthohedron is 436 cm².
We have hundreds of course questions with personalized recommendations + Account 100% premium
Look at the orthohedron shown in the figure below.
Side b is 20% longer than side a.
Side c is 20% longer than side b.
Calculate a, c, and b given that the surface area of the orthohedron is 436 cm².
First, we'll express and in terms of :
Next, substitute these into the surface area formula for a cuboid:
Substitute these into the formula:
Simplify inside the parentheses:
Solve for :
Taking the square root, we find:
Now, find and :
Therefore, the dimensions of the orthohedron are:
, , and .
a=7.06, b=8.47, c=10.17
A cuboid is shown below:
What is the surface area of the cuboid?
Because c is 20% longer than b, not 20% longer than a! First find b = 1.2a, then c = 1.2b = 1.2 × 1.2a = 1.44a. The increases are progressive, not independent.
This would mean your setup is wrong! Check that you've correctly combined like terms and that your surface area formula is 2(ab + bc + ca), not just (ab + bc + ca).
Always express everything in terms of the simplest variable - usually the one without percentage increases. Here, express b and c in terms of a, then solve for a first.
Yes! This is a great checking method. Pick an answer choice for a, calculate b and c, then check if . If it works, you found the right answer!
A rectangular prism has 6 faces: 2 faces of area ab, 2 faces of area bc, and 2 faces of area ca. So total area = 2ab + 2bc + 2ca = 2(ab + bc + ca).
Get unlimited access to all 18 Cuboids questions, detailed video solutions, and personalized progress tracking.
Unlimited Video Solutions
Step-by-step explanations for every problem
Progress Analytics
Track your mastery across all topics
Ad-Free Learning
Focus on math without distractions
No credit card required • Cancel anytime