Lesson 5.105.10 · Part II
Start hereWords, worked example, and sentence starters
Learning target I can find the volume of a rectangular prism, including ones with fractional edge lengths, using base area × height.
Start hereWords for this lesson
Read each word before you begin. Say it out loud.
| Word | What it means | Example |
|---|---|---|
| VolumeSpanish: Volumen | How much space is inside a solid shape. | A box 2 × 1.5 × 1 = 3 ft³ — it holds 3 cubic feet of stuff |
| Rectangular prismSpanish: Prisma rectangular | A solid box shape with six flat rectangle sides. | A tissue box, a fish tank, a brick — all rectangular prisms |
| Cubic unitsSpanish: Unidades cúbicas | The units used to measure space inside, like cubic inches. | 1 ft³ = a cube that is 1 foot on every edge |
| DimensionsSpanish: Dimensiones | How long, how wide, and how tall a shape is. | A box with dimensions 4 × 3 × 2 means l = 4, w = 3, h = 2 |
| Base areaSpanish: Área de la base | The area of the bottom of a solid. Volume = base area × height. | If the base is 6 × 4 = 24 cm² and h = 3, then V = 24 × 3 = 72 cm³ |
Say it and write itSentence starters
Finish each sentence out loud with a partner. Then use them in your writing.
Word bank VolumeRectangular prismCubic unitsDimensionsBase area
Watch outA common mistake
A common mistake in Volume of Rectangular Prisms is rounding a fractional edge length to the nearest whole number before multiplying, instead of using the exact fraction or decimal. For a box that is 2 ft × 1.5 ft × 1 ft, a student might round 1.5 down to 1 and compute 2 × 1 × 1 = 2 ft³, but the correct volume uses the exact edge length: 2 × 1.5 × 1 = 3 ft³ — a full cubic foot larger. Before you submit, ask: 'Did I multiply using the exact fractional or decimal edge length, or did I round it off first?'
Lesson 5.105.10 · Part II
Apply Day · Version ASupported practice
Learning target I can find the volume of a rectangular prism, including ones with fractional edge lengths, using base area × height.
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1Complete each step, then write the final answer.
A box is 3 in long, 2 in wide, and 0.5 in tall. Find its volume.
Show your workHint Find the base area. Then take half of it, because the height is 0.5.
Final answer: -
2Complete each step, then write the final answer.
A box is 4 ft long, 3 ft wide, and 1.5 ft tall. Find its volume.
Show your workHint Find the base area. Then multiply by 1.5.
Final answer: -
3Complete each step, then write the final answer.
A box is 5 m long, 4 m wide, and 1/2 m tall. Find its volume.
Show your workHint Find the base area. Multiplying by 1/2 means taking half.
Final answer:
Lesson 5.105.10 · Part II
Apply Day · Version BCore practice
Learning target I can find the volume of a rectangular prism, including ones with fractional edge lengths, using base area × height.
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1Complete each step, then write the final answer.
Ava finds the volume of a box that is 4 m by 2.5 m by 2 m. She writes 4 + 2.5 + 2 = 8.5. What is the volume?
Show your workFinal answer: -
2Complete each step, then write the final answer.
A box is 2 1/4 in long, 2 in wide, and 4 in tall. Find its volume.
Show your workFinal answer: -
3Complete each step, then write the final answer.
A box is 8 cm long, 3 cm wide, and 2.5 cm tall. Find its volume.
Show your workFinal answer:
Lesson 5.105.10 · Part II
Apply Day · ChallengeExtension
Learning target I can find the volume of a rectangular prism, including ones with fractional edge lengths, using base area × height.
-
1Circle the letter of the best answer. Show how you know.
A container measures 1½ feet long, 2 feet wide, and 3 feet tall. What is its volume?
- A6 cubic feet
- B6½ cubic feet
- C9 cubic feet
- D18 cubic feet
Show your work -
2Complete each step, then write the final answer.
Raj rounds a box that is 2 1/2 cm by 1 1/2 cm by 4 cm to 3 × 2 × 4 = 24. What is the real volume?
Show your workFinal answer: -
3Complete each step, then write the final answer.
A box is 1 1/2 m long, 1 1/2 m wide, and 2 m tall. Find its volume.
Show your workFinal answer: