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5th grade math · Unit 9: Shapes and volume

Find the missing edge

What this lesson shows

120 cubic inches on a 3 by 10 inch base: 120 = 30 × h, so h = 4.

The worked example

The lesson works this one step by step: 10 × 3 × 4. Then your kid tries one like it on paper.

The steps

  1. Find B first
  2. Fill in V = B × h
  3. Divide, then check

Helping at home

Find B, the area of the base, first. Fill in V = B × h with what you know, then divide the volume by B for the height. Check by multiplying back.

If your kid gets stuck

Find B first, then divide the volume by B.

Watch it with Lux

With Lux, this lesson is a narrated video and a printed page your kid works on. Then Lux helps with the same math on their own worksheet, one question at a time.

See how Lux works

Standards

  • Common Core 5.MD.C.5b
    Apply the formulas V = l × w × h and V = b × h for rectangular prisms to find volumes of right rectangular prisms with whole-number edge lengths in the context of solving real world and mathematical problems.
Matches standards in 49 statesSee each state's code

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