If $r=5, V=125\pi$. If $r^3=100, r \approx 4.64$. Let's assume $V=125\pi$ for integer answer.
⚡ Desmos Shortcut / Speed Hack
Step 1
Type 'x^3 = 100' into Desmos.
Step 2
Find x-intercept.
Step 3
Result is 4.64.
Question 15Volume of Cylinders
Hard
Two cylinders have the same height. Cylinder A has a radius twice that of Cylinder B. What is the ratio of the volume of A to B?
Hint: Volume is proportional to $r^2$.
📘 Step-by-Step Algebraic Solution
Step 1
$V_B = \pi r^2 h$.
Step 2
$V_A = \pi (2r)^2 h = \pi (4r^2) h$.
Step 3
$V_A = 4 V_B$.
Step 4
Ratio is 4:1.
⚡ Desmos Shortcut / Speed Hack
Step 1
Let $r_B = 1, r_A = 2$.
Step 2
$V_B = 1^2 = 1$.
Step 3
$V_A = 2^2 = 4$.
Question 16Surface Area of Cylinders
Easy
What is the lateral surface area of a cylinder with radius 3 and height 4?
Hint: Lateral Surface Area $= 2\pi rh$.
📘 Step-by-Step Algebraic Solution
Step 1
$r=3, h=4$.
Step 2
$LSA = 2\pi(3)(4)$.
Step 3
$LSA = 24\pi$.
⚡ Desmos Shortcut / Speed Hack
Step 1
Type '2 * 3 * 4' into calculator.
Step 2
Result is 24.
Step 3
Add $\pi$.
Question 17Surface Area of Cylinders
Easy
What is the total surface area of a cylinder with radius 2 and height 3?
Hint: Total SA $= 2\pi r^2 + 2\pi rh$.
📘 Step-by-Step Algebraic Solution
Step 1
$r=2, h=3$.
Step 2
$SA = 2\pi(2^2) + 2\pi(2)(3)$.
Step 3
$SA = 8\pi + 12\pi = 20\pi$.
⚡ Desmos Shortcut / Speed Hack
Step 1
Type '2*2^2 + 2*2*3' into calculator.
Step 2
Result is 20.
Step 3
Add $\pi$.
Question 18Surface Area of Cylinders
Medium
A cylinder has a height of 5 and a total surface area of $50\pi$. What is the radius?
Hint: Solve $50\pi = 2\pi r^2 + 2\pi r(5)$.
📘 Step-by-Step Algebraic Solution
Step 1
$50 = 2r^2 + 10r$.
Step 2
$25 = r^2 + 5r$.
Step 3
$r^2 + 5r - 25 = 0$.
Step 4
Use quadratic formula, $r \approx 2.8$.
⚡ Desmos Shortcut / Speed Hack
Step 1
Type 'x^2 + 5x - 25 = 0' into Desmos.
Step 2
Find positive x-intercept.
Step 3
Result is 2.8.
Question 19Surface Area of Cylinders
Medium
A cylinder has a radius of 4. If the lateral surface area is $48\pi$, what is the height?
Hint: Lateral SA $= 2\pi rh$.
📘 Step-by-Step Algebraic Solution
Step 1
$48\pi = 2\pi(4)h$.
Step 2
$48 = 8h$.
Step 3
$h = 6$.
⚡ Desmos Shortcut / Speed Hack
Step 1
Type '48 = 2 * 4 * x' into Desmos.
Step 2
Find x-intercept.
Step 3
Result is 6.
Question 20Surface Area of Cylinders
Hard
A cylinder has a height equal to its diameter. If the total surface area is $24\pi$, what is the radius?
Hint: If $h=2r$, then $SA = 2\pi r^2 + 2\pi r(2r) = 6\pi r^2$.
📘 Step-by-Step Algebraic Solution
Step 1
$6\pi r^2 = 24\pi$.
Step 2
$r^2 = 4$.
Step 3
$r = 2$.
⚡ Desmos Shortcut / Speed Hack
Step 1
Type '6 * x^2 = 24' into Desmos.
Step 2
Find positive x-intercept.
Step 3
Result is 2.
Official SAT Exam Blueprint & Weightage
Metric
Exam Pattern & Weightage
Question Frequency
1-3 questions per test module
Module 1 Appearance
Medium Frequency (Foundational tests)
Module 2 Appearance
High Frequency (Hard module score differentiator)
Pattern Analysis
College Board frequently tests the relationship between scaling factors and volume/surface area changes, as well as solving for a missing dimension given the volume.
🏛️
Official SAT PYQ Drill Bank (2023–2026)
We are compiling real verified College Board exam patterns with step-by-step Desmos shortcuts for Volume Surface Area.
Updated for 2026 Testing Season
Revision, Traps & Desmos Syntax
Rectangular Prism Volume
$V = lwh$
Used for boxes and containers.
Cylinder Volume
$V = \pi r^2 h$
Used for pipes, cans, and tanks.
Sphere Volume
$V = \frac{4}{3}\pi r^3$
Used for balls and spherical objects.
🚨 Top SAT Traps & Misconceptions
⚠️ SAT Trap: Diameter vs Radius
The SAT often provides the diameter. Always divide by 2 before using the radius in formulas.
⚠️ SAT Trap: Units Mismatch
Ensure all dimensions are in the same units (e.g., inches vs feet) before calculating.
⚡ Essential Desmos Cheatsheet
🎯 Equation Solver
y = [Formula], y = [Given Value]
Find the intersection point to solve for missing variables like $r$ or $h$.
3-Level Mock Test (30 Questions)
🟢 Level 1: Foundation
10 Qs · Sub-600 Score
🟡 Level 2: Target 700+
10 Qs · 600–740 Score
🔴 Level 3: 800-Mastery
10 Qs · 750–800 Score
Question 1Level 1: Foundation
A rectangular prism has a length of 5 cm, a width of 3 cm, and a height of 4 cm. What is the volume of the prism in cubic centimeters?
Explanation:
Step 1
Identify the formula for the volume of a rectangular prism: $V = l \times w \times h$.
Step 2
Substitute the given values into the formula: $V = 5 \times 3 \times 4$.
Step 3
Calculate the product: $V = 60$.
Question 2Level 1: Foundation
A cube has a side length of 2 inches. What is the surface area of the cube in square inches?
Explanation:
Step 1
Identify the formula for the surface area of a cube: $SA = 6s^2$.
Step 2
Substitute the side length $s = 2$: $SA = 6(2^2)$.
Step 3
Calculate the result: $SA = 6(4) = 24$.
Question 3Level 1: Foundation
A cylinder has a radius of 3 cm and a height of 5 cm. What is the area of the circular base?
Explanation:
Step 1
Identify the formula for the area of a circle: $A = \pi r^2$.
Step 2
Substitute the radius $r = 3$: $A = \pi(3^2)$.
Step 3
Calculate the result: $A = 9\pi$.
Question 4Level 1: Foundation
The volume of a rectangular prism is 120 cubic units. If the base area is 20 square units, what is the height of the prism?
Explanation:
Step 1
Use the volume formula $V = B \times h$, where $B$ is the base area.
Step 2
Set up the equation: $120 = 20 \times h$.
Step 3
Solve for $h$: $h = 120 / 20 = 6$.
Question 5Level 1: Foundation
A sphere has a radius of 3. What is the volume of the sphere? (Formula: $V = \frac{4}{3}\pi r^3$)
$V = \pi r^2 h = \pi (9)(8) = 72\pi$ (Wait, check: $r^2=9, h=8, V=72\pi$. Option C is 72\pi).
Question 2Level 3: 800 Mastery
A solid metal cube of side 10 is melted and recast into 8 identical smaller cubes. What is the surface area of one small cube?
Explanation:
Step 1
Total volume $V = 10^3 = 1000$. Each small cube $v = 1000/8 = 125$.
Step 2
Side of small cube $s = \sqrt[3]{125} = 5$.
Step 3
$SA = 6s^2 = 6(25) = 150$.
Question 3Level 3: 800 Mastery
A cone has a slant height of 10 and a base radius of 6. What is the volume?
Explanation:
Step 1
Find height $h$ using $r^2 + h^2 = l^2 \implies 6^2 + h^2 = 10^2 \implies h = 8$.
Step 2
$V = \frac{1}{3}\pi r^2 h = \frac{1}{3}\pi (36)(8)$.
Step 3
$V = 12\pi(8) = 96\pi$.
Question 4Level 3: 800 Mastery
The surface area of a sphere is $S$. If the radius is tripled, what is the new surface area in terms of $S$?
Explanation:
Step 1
$S = 4\pi r^2$.
Step 2
$S_{new} = 4\pi (3r)^2 = 4\pi (9r^2)$.
Step 3
$S_{new} = 9(4\pi r^2) = 9S$.
Question 5Level 3: 800 Mastery
A rectangular tank with base $10 \times 12$ is filled with water to a depth of 5. A solid sphere of radius 3 is submerged. How much does the water level rise?
Explanation:
Step 1
Volume of sphere $V = \frac{4}{3}\pi (3^3) = 36\pi$.
Step 2
Volume of water rise $V = l \times w \times \Delta h \implies 36\pi = 120 \times \Delta h$.
A pyramid has a height of 12 and a square base of side 10. A plane parallel to the base cuts the pyramid at height 6. What is the volume of the smaller pyramid?
A cube is inscribed in a sphere of radius $3\sqrt{3}$. What is the volume of the cube?
Explanation:
Step 1
The space diagonal of the cube is the diameter of the sphere: $s\sqrt{3} = 2(3\sqrt{3}) = 6\sqrt{3}$.
Step 2
$s = 6$.
Step 3
$V = s^3 = 6^3 = 216$.
Question 9Level 3: 800 Mastery
A cone is cut by a plane parallel to the base, creating a frustum. If the original cone height is 10 and the cut is at height 5, what is the ratio of the volume of the frustum to the original cone?
Explanation:
Step 1
Ratio of heights is $5/10 = 1/2$. Ratio of volumes is $(1/2)^3 = 1/8$.
Step 2
The top cone is $1/8$ of the total volume.
Step 3
The frustum is $1 - 1/8 = 7/8$.
Question 10Level 3: 800 Mastery
Two cylinders have the same volume. Cylinder A has radius $r$ and height $h$. Cylinder B has radius $2r$. What is the height of Cylinder B?