What does double mean in math?

What does “double” mean in math? Is it to multiply the number by two or by the number itself? By reading this article, you will be able to get all your questions answered and discover new ways to use the math word double.

What does double mean in math?

In mathematics, the term “double” refers to two times. The word double in math indicates that there are two lots of the same amount.

To find the double of a number, you can multiply the initial number by 2. For example, if you want to know the double of 3, you have to multiply 3 by 2.

Check Our What does at least mean in math?

You can double a number in another way. You can just add the same number to the initial number. For example, if you want to know the double of 3, you can add 3 to 3.

Even percentages can be used to find the double of a number. For example, if you want to know the double of 3, you can increase 3 by 100% or multiply by 200%.

or

Check Our What does c mean in math?

In summary, to double a number, you can use any of the following methods.

• Multiply the initial number by 2
• Add the same number to the initial number
• Increase the initial number by 100%
• Multiply the initial number by 200%

What is a two-times table?

Two times table is important when you are learning “double” in math. The purpose of the 2 multiplication table is to double the number.

Check Our What does a circle with a line through it mean in math?

What does near double strategy?

The near double strategy in mathematics refers to an addition fact technique where you add to or deduct from a doubles fact that you already know to answer another fact.

You can use either the doubles + (plus) approach or the doubles – (minus) approach to add any two consecutive numbers.

The doubles + (plus) approach in the near-double strategy

The doubles + (plus) approach in the near double strategy is used when two consecutive numbers are in ascending order. We will learn this using an example.

Example:

Assume Milly has three apples and Sam has four apples. You want to know how many apples they have in total. So, you must add 3 and 4 to find the total number of apples.

We already know that doubling 3 equals 6. So, you divide Sam’s 4 apples into 3 and 1.

The required total is now one greater than double. So, you can rewrite the above as follows.

Now, you can get the total number of apples as given below.

Check Our What does dot mean in math?

I will explain it again. 3 and 4 are consecutive numbers (i.e. 4 comes after 3). 4 is 1 number greater than 3. So, you double the number 3 and add 1 to arrive at the answer for 3+4.

Example:

Find the answer.

   8+9

   20+21

Solution:

8+9=(8×2)+1=16+1=17

20+21=(20×2)+1=40+1=41

The doubles – (minus) approach in the near double strategy

The doubles – (minus) approach in the near double strategy is used when two consecutive numbers are in descending order. We will learn this using an example.

Check Our What does double bracket mean in math?

Example:

Assume Henry bought four toffees and Jane bought three toffees. You want to know how many toffees they have bought in total. So, you must add 4 and 3 to find the total number of toffees.

We already know that doubling 4 equals 8. So, you double make Jane’s number of toffees the same as Henry’s and deduct 1.

The required total is now one less than double. So, you can rewrite the above as follows.

Now, you can get the total number of apples as given below.

I will explain it again. 4 and 3 are consecutive numbers (i.e. 4 comes before 3). 4 is 1 number less than 3. So, you double the number 4 and deduct 1 to arrive at the answer for 4+3.

Example:

Find the answer.

  9+8

  21+20

Solution:

   9+8=(9×2)-1=18-1=17

   21+20=(21×2)-1=42-1=41

Check Our What does KCF mean in math?

What does double in subtraction?

Doubles facts can also be used to answer subtraction problems. We will learn this using an example.

Example:

Assume you have eight croissants. You and your friends ate 4 of the 8 croissants. How many croissants are left? You must subtract 4 from 8 to determine how many croissants are still left.

You are aware that 8 is equal to the double 4. In other words, you know your answer is 8 if you add 4 to 4.

So, if you subtract four from eight, the result is four.

Example:

Find the answer.

• 16-8
• 10-5

Solution:

Since

8+8=16

16-8=8

Since

5+5=10

10-5=5

Check Our What does m mean in math?

What does double-double mean in math?

In mathematics, the “double-double” term is used to multiply by 4. You already know that the word “double” in math is to multiply by two. Now the word “double” is written twice. This means that you must multiply the original number by 2 twice.

We will learn this using an example.

Example:

Let’s say that Kate has put 8 coins in her pocket 4 times. You want to know how many coins are in the pocket now. So, you have to multiply 8 by 4. Now, you can use the double-double concept in math. So, you double the 8 twice. In other words, you multiply 8 by 2 twice.

What does double double-double mean in math?

In mathematics, the “double double-double” term is used to multiply by 8. Now the word “double” is written three times. This means that you must multiply the original number by 2 three times.

We will learn this using an example.

Example:

Let’s say that Kate has put 8 coins in her pocket 8 times. You want to know how many coins are in the pocket now. So, you have to multiply 8 by 8. Now, you can use the double double-double concept in math. So, you double the 8 three times. In other words, you multiply 8 by 2 three times.

Check Our What does per mean in math?

What are the other usages of word double in math?

In mathematics, the terms “double root”, “double square number” and “double factorial” are also often used.

Double root

No x-axis crossing occurs at a double root. It merely makes contact with it.

Double square number

A double-square number in mathematics is a number that can be written as the summation of two perfect squares.

Example:

13 is a double-square number as it can be shown as follows.

13=2^2+3^2

Double factorial

In the multifactorial, the double factorial is a unique instance. It is denoted by inserting 2 factorial notations.

Frequently asked questions