What is the cube root of 81?

6 Answers
my question: what is the cube root of 81?, please answer if you can, regards

The cubed root of 81 can be written as 81^(1/3). The easiest way to derive the answer is, unfortunately, to use a calculator which gives us the answer of 4.3267... Meaning that the cubed root is not a perfect cube root.

In contrast, 8 has a perfect cube root of 2. Meaning that 2^2 = 2 * 2 * 2 = 8. Most numbers will not have perfect cube roots and it would actually be quite interesting to know why you are seeking the cube root of 81. When I see the number 81, I would rather think about the square root of 81 which is 9 and more commonly seen in various questions.


The cubed root of 27 is three: 3 x 3 x 3 = 27. 81 is not a perfect cube, so the answer to this question is going to be a decimal number. Since you might already know that 4 cubed is 64 and that 5 cubed is 125, the cube of 81 is going to fall somewhere between 4 and 5.

Since no-one knows how to do the math anymore, you have to use a calculator to find the cubed root of 81. The cubed root of 81 = 4.32674871092


The number I come up with is 4.3267487109222251469649149323403

Rounded off to 4.327 and then cubed yields = 81.014 Close enough?


The number when multiplied by itself 3 times will give 81. This can be found using the cube button on a scientific calculator.


81 is not a perfect cube root. Its cube root is 4.3267487


4.3267487 is pretty close or 3x cubed root of 3