6th grade · Math · Unit 8 of 17
Volume & Capacity
Cubes, liters and milliliters
What your child practices
Finding the volume of rectangular prisms, converting between liters and milliliters, and connecting volume to capacity (1 cm³ holds 1 mL).
Maine Learning Results learning standard: 6.G.A.2 · volume of right rectangular prisms
How we explain it
Children can open this short lesson before they practice.
- Volume is the space inside a solid, in cubic units like cm³.
- Volume of a rectangular prism = length × width × height.
- 1 cm³ holds 1 mL. 1000 mL is 1 L.
Example: A box is 5 cm long, 4 cm wide and 3 cm high. What is its volume? 5 × 4 = 20. 20 × 3 = 60. Answer: 60 cm³
Volume & Capacity in Maine
In the Maine Learning Results, this is unit 8 of 17 in 6th grade Math, after Perimeter & Area and before Integers & Decimals.
Gradelings describes a child's practice on this unit as Beginning, Approaching, Meeting or Exceeding (Four practice steps). That reflects practice, not a report-card mark: the teacher decides the mark.
Source: Maine Department of Education
Sample questions
A taste of this unit. In the app, questions change every time and get easier or harder to match your child.
Question 1
A rectangular prism is 10 cm long, 5 cm wide and 7 cm high. What is its volume?
answer boxcm³
350 cm³
Hint: Volume = length × width × height. Multiply two of the numbers first, then multiply by the third.
Question 2
Which box has the greatest volume?
- 5 cm × 7 cm × 8 cm
- 5 cm × 9 cm × 6 cm
- 3 cm × 8 cm × 5 cm
- 4 cm × 3 cm × 5 cm
5 cm × 7 cm × 8 cm
Hint: Work out each volume (length × width × height), then compare. A box can be longer but still hold less.
Question 3
A box has a volume of 540 cm³. It is 9 cm long and 10 cm wide. How high is it?
answer boxcm
6 cm
Hint: Volume = length × width × height. The base is 9 × 10 = 90 cm², so divide the volume by 90.
Question 4
This is the bottom layer of a box packed with 1 cm cubes. The box is 2 layers high. What is the volume of the box?
🧊🧊🧊🧊🧊🧊🧊🧊🧊🧊🧊🧊🧊🧊🧊🧊🧊🧊🧊🧊🧊🧊🧊🧊🧊🧊🧊🧊🧊🧊answer boxcm³
60 cm³
Hint: Find the number of cubes in one layer (rows × columns), then multiply by the number of layers.
Question 5
Write 250 mL in liters.
answer boxL
0.25 L
Hint: 1 L = 1000 mL. To change liters to milliliters, multiply by 1000. To change milliliters to liters, divide by 1000.
Question 6
Which unit is best for measuring the capacity of a bathtub?
- liters (L)
- centimeters (cm)
- kilograms (kg)
- milliliters (mL)
liters (L)
Hint: Capacity is how much a container holds. A bathtub holds a lot of water, so use a big capacity unit.