RootsCube roots
Name: Date:
Find each cube root.
1216 =
227 =
31728 =
4512 =
5729 =
664 =
Cube roots worksheets
A cube root asks which number, multiplied by itself three times, gives this one. These free printable worksheets use perfect cubes only, so every answer comes out whole.
Kid stuck on one? You don’t just get the sheet.
Cube roots
The answer key prints on a separate page.
What's on this sheet
∛216 = 6 because 6 × 6 × 6 = 216. The list of cubes is much shorter than the list of squares — 1, 8, 27, 64, 125, 216, 343, 512, 729, 1000 — and knowing those ten covers most of what a course will ask for.
Why this sheet works
The most common mistake is dividing by three. ∛27 is 3, not 9, and a child who has only ever seen square roots will sometimes halve or third the number instead of looking for the factor that appears three times. Saying "what times itself times itself" out loud is usually enough to fix it.
How this one works
One question from this sheet, worked through a step at a time.
∛216
∛216=▢
∛216is under∛1000 = 10
∛216=6
6 × 6 × 6=216
∛216=6
- ∛ asks a question: which number, used three times as a factor, gives 216? It is not an instruction to divide 216 by 3 — that is the mistake this symbol collects.
- First the size: 216 is under 1000, and 1000 is 10³ — so the cube root is a single digit, somewhere from 1 to 9.
- Now the last digit. 216 ends in 6, and the only digit whose cube ends in 6 is 6. So the answer is 6.
- Check it: 6 × 6 × 6 = 216. So ∛216 = 6.