Last updated on May 30th, 2025
When a number is multiplied by itself thrice, the resultant number is called the cube of a number. Cubing is used in comparing sizes of objects or things with cubic measurements. In this topic, we shall learn about the cube of 20.
A cube number is a value obtained by raising a number to the power of 3, or by multiplying the number by itself three times. When you cube a positive number, the result is always positive. When you cube a negative number, the result is always negative. This is because a negative number by itself three times results in a negative number.
The cube of 20 can be written as 20³, which is the exponential form. Or it can also be written in arithmetic form as, 20 × 20 × 20.
In order to check whether a number is a cube number or not, we can use the following three methods, such as multiplication method, a factor formula (a³), or by using a calculator. These three methods will help kids to cube the numbers faster and easier without feeling confused or stuck while evaluating the answers.
The multiplication method is a process in mathematics used to find the product of two numbers or quantities by combining them through repeated addition. It is a fundamental operation that forms the basis for more complex mathematical concepts.
Step 1: Write down the cube of the given number. 20³ = 20 × 20 × 20
Step 2: You get 8,000 as the answer. Hence, the cube of 20 is 8,000.
The formula (a + b)³ is a binomial formula for finding the cube of a number. The formula is expanded as a³ + 3a²b + 3ab² + b³.
Step 1: Split the number 20 into two parts, as 15 and 5. Let a = 15 and b = 5, so a + b = 20
Step 2: Now, apply the formula (a + b)³ = a³ + 3a²b + 3ab² + b³
Step 3: Calculate each term
a³ = 15³
3a²b = 3 × 15² × 5
3ab² = 3 × 15 × 5²
b³ = 5³
Step 4: Add all the terms together:
(a + b)³ = a³ + 3a²b + 3ab² + b³
(15 + 5)³ = 15³ + 3 × 15² × 5 + 3 × 15 × 5² + 5³
20³ = 3375 + 3375 + 1125 + 125
20³ = 8000
Step 5: Hence, the cube of 20 is 8,000.
To find the cube of 20 using a calculator, input the number 20 and use the cube function (if available) or multiply 20 × 20 × 20. This operation calculates the value of 20³, resulting in 8,000. It’s a quick way to determine the cube without manual computation.
Step 1: Ensure the calculator is functioning properly.
Step 2: Press 2 followed by 0
Step 3: If the calculator has a cube function, press it to calculate 20³.
Step 4: If there is no cube function on the calculator, simply multiply 20 three times manually.
Step 5: The calculator will display 8,000.
There are some typical errors that kids might make during the process of cubing a number. Let us take a look at five of the major mistakes that kids might make:
What is the cube and cube root of 20?
The cube of 20 is 8,000 and the cube root of 20 is approximately 2.714.
First, let’s find the cube of 20.
We know that the cube of a number, such that x³ = y Where x is the given number, and y is the cubed value of that number
So, we get 20³ = 8,000
Next, we must find the cube root of 20 We know that the cube root of a number ‘x’, such that ∛x = y Where ‘x’ is the given number, and y is the cube root value of the number
So, we get ∛20 ≈ 2.714
Hence the cube of 20 is 8,000 and the cube root of 20 is approximately 2.714.
If the side length of a cube is 20 cm, what is the volume?
The volume is 8,000 cm³.
Use the volume formula for a cube V = Side³.
Substitute 20 for the side length: V = 20³ = 8,000 cm³.
How much larger is 20³ than 10³?
20³ – 10³ = 7,900.
First, find the cube of 20³, that is 8,000
Next, find the cube of 10³, which is 1,000
Now, find the difference between them using the subtraction method.
8,000 – 1,000 = 7,000
Therefore, 20³ is 7,000 larger than 10³.
If a cube with a side length of 20 cm is compared to a cube with a side length of 5 cm, how much larger is the volume of the larger cube?
The volume of the cube with a side length of 20 cm is 8,000 cm³.
To find its volume, we multiply the side length by itself three times (since it’s a 3-dimensional object).
Cubing 20 means multiplying 20 by itself three times: 20 × 20 = 400, and then 400 × 20 = 8,000.
The unit of volume is cubic centimeters (cm³), because we are calculating the space inside the cube.
Therefore, the volume of the cube is 8,000 cm³.
Estimate the cube of 19.9 using the cube of 20.
The cube of 19.9 is approximately 8,000.
First, identify the cube of 20, The cube of 20 is 20³ = 8,000.
Since 19.9 is only a tiny bit less than 20, the cube of 19.9 will be almost the same as the cube of 20.
The cube of 19.9 is approximately 8,000 because the difference between 19.9 and 20 is very small.
So, we can approximate the value as 8,000.
Jaskaran Singh Saluja is a math wizard with nearly three years of experience as a math teacher. His expertise is in algebra, so he can make algebra classes interesting by turning tricky equations into simple puzzles.
: He loves to play the quiz with kids through algebra to make kids love it.