Last updated on May 26th, 2025
When a number is multiplied by itself thrice, the resultant number is called the cube of a number. Cubing is used when comparing sizes of objects or things with cubic measurements. In this topic, we shall learn about the cube of 3.2.
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 multiplied by itself three times results in a negative number.
The cube of 3.2 can be written as 3.2³, which is the exponential form. Or it can also be written in arithmetic form as 3.2 × 3.2 × 3.2.
To check whether a number is a cube number or not, we can use the following three methods: the 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 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. 3.2³ = 3.2 × 3.2 × 3.2
Step 2: You get approximately 32.768 as the answer. Hence, the cube of 3.2 is approximately 32.768.
The formula for the cube of a binomial (a + b)³ is expanded as a³ + 3a²b + 3ab² + b³.
Step 1: Split the number 3.2 into two parts, such as a = 3 and b = 0.2, so a + b = 3.2.
Step 2: Now apply the formula (a + b)³ = a³ + 3a²b + 3ab² + b³.
Step 3: Calculate each term: a³ = 3³ 3a²b = 3 × 3² × 0.2 3ab² = 3 × 3 × 0.2² b³ = 0.2³
Step 4: Add all the terms together:
(a + b)³ = a³ + 3a²b + 3ab² + b³
(3 + 0.2)³ = 3³ + 3 × 3² × 0.2 + 3 × 3 × 0.2² + 0.2³ 3.2³
= 27 + 5.4 + 0.36 + 0.008 3.2³
= 32.768
Step 5: Hence, the cube of 3.2 is approximately 32.768.
To find the cube of 3.2 using a calculator, input the number 3.2 and use the cube function (if available) or multiply 3.2 × 3.2 × 3.2. This operation calculates the value of 3.2³, resulting in approximately 32.768. It’s a quick way to determine the cube without manual computation.
Step 1: Ensure the calculator is functioning properly.
Step 2: Press 3.2
Step 3: If the calculator has a cube function, press it to calculate 3.2³.
Step 4: If there is no cube function on the calculator, simply multiply 3.2 three times manually.
Step 5: The calculator will display approximately 32.768.
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 3.2?
The cube of 3.2 is approximately 32.768, and the cube root of 3.2 is approximately 1.464.
First, let’s find the cube of 3.2.
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 3.2³ = approximately 32.768.
Next, we must find the cube root of 3.2.
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 ∛3.2 = approximately 1.464.
Hence, the cube of 3.2 is approximately 32.768, and the cube root of 3.2 is approximately 1.464.
If the side length of the cube is 3.2 cm, what is the volume?
The volume is approximately 32.768 cm³.
Use the volume formula for a cube V = Side³.
Substitute 3.2 for the side length: V = 3.2³ = approximately 32.768 cm³.
How much larger is 3.2³ than 2.8³?
3.2³ – 2.8³ = approximately 15.928.
First, find the cube of 3.2³, which is approximately 32.768.
Next, find the cube of 2.8³, which is approximately 16.84.
Now, find the difference between them using the subtraction method.
32.768 – 16.84 = approximately 15.928.
Therefore, 3.2³ is approximately 15.928 larger than 2.8³.
If a cube with a side length of 3.2 cm is compared to a cube with a side length of 1.5 cm, how much larger is the volume of the larger cube?
The volume of the cube with a side length of 3.2 cm is approximately 31.368 cm³ larger.
To find its volume, we multiply the side length by itself three times (since it’s a 3-dimensional object).
Cubing 3.2 means multiplying 3.2 by itself three times:
3.2 × 3.2 = 10.24, and then 10.24 × 3.2 = approximately 32.768.
For 1.5, 1.5 × 1.5 = 2.25, and then 2.25 × 1.5 = approximately 3.375.
Now, subtract the smaller volume from the larger volume:
32.768 – 3.375 = approximately 31.368.
Therefore, the volume of the larger cube is approximately 31.368 cm³ larger.
Estimate the cube of 3.1 using the cube of 3.2.
The cube of 3.1 is approximately 29.791.
First, identify the cube of 3.2,
The cube of 3.2 is 3.2³ = approximately 32.768.
Since 3.1 is only a little less than 3.2, we can estimate the cube of 3.1 as slightly less than the cube of 3.2.
The cube of 3.1 is approximately 29.791.
So, we can approximate the value as 29.791.
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.