This grade 5 volume worksheet answer key solves all 22 problems of the volume of rectangular prisms worksheet step by step.
Each solution shows the formula, the substituted numbers, and the answer with its cubic unit. If your answer differs, check that you multiplied all three edges and wrote cubic units, not square units.
Grade 5 Volume Worksheet Answer Key: problems 1–5
Problem 1: Counting unit cubes
Each layer has \(3 \times 2 = 6\) cubes, and there are 2 layers: \(6 \times 2 = 12\).
Answer: 12 cubic units.
Problem 2: Counting layers
One layer has \(4 \times 3 = 12\) cubes. There are 2 layers. Volume: \(12 \times 2 = 24\).
Answer: 12 cubes per layer, 2 layers, 24 cubic units.
Problem 3: Volume in centimeters
\(V = l \times w \times h = 5 \times 4 \times 3 = 60\).
Answer: \(60\text{ cm}^{3}\).
Problem 4: Volume in feet
\(V = 8 \times 2 \times 6 = 16 \times 6 = 96\).
Answer: \(96\text{ ft}^{3}\).
Problem 5: Using base area
\(V = B \times h = 20 \times 7 = 140\).
Answer: \(140\text{ in}^{3}\).
Grade 5 Volume Worksheet Answer Key: problems 6–10
Problem 6: Volume of a cube
All three edges are 6 in: \(V = 6 \times 6 \times 6 = 36 \times 6 = 216\).
Answer: \(216\text{ in}^{3}\).
Problem 7: Base first, then height
\(B = 7 \times 5 = 35\) square meters. \(V = 35 \times 4 = 140\).
Answer: B = \(35\text{ m}^{2}\); V = \(140\text{ m}^{3}\).
Problem 8: Missing height
\(6 \times 5 \times h = 90\), so \(30 \times h = 90\). Since \(30 \times 3 = 90\), \(h = 3\).
Answer: \(3\text{ cm}\).
Problem 9: Height from base area
\(36 \times h = 144\), so \(h = 144 : 36 = 4\).
Answer: \(4\text{ ft}\).
Problem 10: Missing length
\(l \times 4 \times 5 = 120\), so \(l \times 20 = 120\) and \(l = 6\).
Answer: \(6\text{ in}\).
Grade 5 Volume Worksheet Answer Key: problems 11–15
Problem 11: Which holds more
A: \(6 \times 4 \times 5 = 120\). B: \(7 \times 3 \times 6 = 126\). Difference: \(126 – 120 = 6\).
Answer: Prism B is greater by \(6\text{ in}^{3}\).
Problem 12: Cubes in layers
\(15 \times 4 = 60\).
Answer: 60 cubic units.
Problem 13: Choose the unit
\(10 \times 6 \times 4 = 240\). Volume uses cubic units.
Answer: \(240\text{ in}^{3}\).
Problem 14: Composite solid, two parts
Blue: \(4 \times 3 \times 3 = 36\). Orange: \(3 \times 3 \times 1 = 9\). Total: \(36 + 9 = 45\).
Answer: \(45\text{ ft}^{3}\).
Problem 15: Staircase solid
Step 1: \(2 \times 4 \times 1 = 8\). Step 2: \(2 \times 4 \times 2 = 16\). Step 3: \(2 \times 4 \times 3 = 24\).
Total: \(8 + 16 + 24 = 48\).
Answer: \(48\text{ ft}^{3}\).
Grade 5 Volume Worksheet Answer Key: problems 16–20
Problem 16: Packing a box
Each cube is \(1\text{ in}^{3}\). \(12 \times 9 \times 6 = 108 \times 6 = 648\).
Answer: 648 cubes.
Problem 17: Check a prism
\(5 \times 3 \times 2 = 15 \times 2 = 30\).
Answer: Yes; the product of the three edges is 30 cubic units.
Problem 18: Sandbox
Volume: \(8 \times 5 \times 1 = 40\) cubic feet. Bags: \(40 : 2 = 20\).
Answer: 20 bags.
Problem 19: Fish tank
Water: \(24 \times 12 \times 8 = 288 \times 8 = 2{,}304\). Full tank: \(288 \times 10 = 2{,}880\). More: \(2{,}880 – 2{,}304 = 576\).
Answer: \(2{,}304\text{ in}^{3}\) of water; \(576\text{ in}^{3}\) more.
Problem 20: Storage boxes
First box: \(6 \times 4 \times 3 = 72\). Second box: \(4 \times 4 \times 2 = 32\). Total: \(72 + 32 = 104\).
Answer: \(104\text{ ft}^{3}\).
Grade 5 Volume Worksheet Answer Key: problems 21–22
Problem 21: Filling a pool
Volume: \(15 \times 10 \times 4 = 600\) cubic feet. Time: \(600 : 50 = 12\).
Answer: 12 hours.
Problem 22: Moving truck
Cargo space: \(10 \times 8 \times 6 = 480\). One box: \(2 \times 2 \times 2 = 8\). \(480 : 8 = 60\).
Answer: 60 boxes.
How to use this grade 5 volume worksheet answer key
Read this grade 5 volume worksheet answer key after trying each problem yourself, and redo any problem you missed.
See every chapter on the Grade 5 math page.