How To Completely Reduce (Simplify) the Fraction 21/7 to the Lowest Terms, Its Simplest Equivalent Form, Irreducible, With the Smallest Possible Numerator and Denominator, That Are Prime to Each Other? Write the Result as an Improper Fraction, as an Integer and as a Percentage

Reduce (simplify) the fraction: 21/7

Detailed calculations below:

Fractions, brief introduction

A fraction consists of two numbers and the fraction bar: 21/7


The number above the fraction bar is the numerator: 21


The number under the fraction bar is the denominator: 7


The fraction bar means that the two numbers divide themselves:
21/7 = 21 ÷ 7


Divide the numerator by the denominator to get the value of the fraction:
The value = 21 ÷ 7


Percentages, short introduction

'Percent, p%' means 'p out of one hundred':


p% = 'p out of one hundred',


p% = p/100 = p ÷ 100


Note:

The fraction 100/100 = 100 ÷ 100 = 100% = 1


Multiply a number by the fraction 100/100,
... and its value will not change.



To completely reduce (simplify) a fraction to its lowest terms, divide the numerator and the denominator of the fraction by their greatest (highest) common factor (divisor), gcf (hcf, gcd)

To calculate the greatest (highest) common factor (divisor), gcf (hcf, gcd), we perform the prime factorization of the two numbers.


The prime factorization of the two numbers:

The prime factorization of a number: finding the prime numbers that multiply together to make that number.


21 = 3 × 7
21 is not a prime number but a composite one.

7 is a prime number and cannot be broken down into other prime factors.


* The natural numbers that are only divisible by 1 and themselves are called prime numbers. A prime number has exactly two factors: 1 and itself.

* A composite number is a natural number that has at least one other factor than 1 and itself.



Calculate the greatest (highest) common factor (divisor), gcf (hcf, gcd):

Multiply all the common prime factors, taken by their smallest exponents (powers).

gcf, hcf, gcd (21; 7) = 7



Divide the numerator and the denominator of the fraction by their greatest (highest) common factor (divisor), gcf (hcf, gcd).

21/7 =


(3 × 7)/7 =


((3 × 7) ÷ 7) / (7 ÷ 7) =


3/1 =


3


If the denominator of the fraction is 1, it can be omitted.

The fraction is now completely reduced (simplified) to its lowest terms.

A fraction that is completely reduced (simplified) to its lowest terms, to its basic representation, to its simplest form:

It is a fraction that can no longer be reduced.

In other words, it is a fraction with the smallest possible numerator and denominator.


A fully reduced fraction is called an irreducible fraction and its numerator and denominator are coprime numbers.

3 = 3/1 is an improper fraction.

An improper fraction: the numerator is greater than or equal to the denominator.


Rewrite the result. This continues below...

Rewrite the result.

As an improper fraction
(the denominator = 1):

3 = 3/1


As a percentage:

Multiply the fraction's value by the fraction 100/100

3 =


3 × 100/100 =


(3 × 100)/100 =


300/100 =


300%


The final answer:
:: Written in three ways ::

As an improper fraction:
21/7 = 3/1

As an integer:
21/7 = 3

As a percentage:
21/7 = 300%

Other similar operations with fractions reducing (simplification):


Online Calculator: Completely reduce (simplify) fraction to the lowest terms

To fully reduce (simplify) fractions to the lowest terms:

Divide the numerator and denominator of the fraction by their greatest (highest) common factor (divisor), gcf (hcf, gcd).

Result written as a proper or an improper fraction, as a mixed number, as a decimal or an integer and as a percentage.

The latest 10 fractions that have been fully reduced (simplified) to their lowest terms (to their simplest form, the smallest possible numerator and denominator)

Completely reduce (simplify) the fraction 21 / 7 to the lowest terms (to its simplest form, irreducible - the smallest possible numerator and denominator) Sep 22 09:22 UTC (GMT)
Completely reduce (simplify) the fraction 33 / 2,452,989 to the lowest terms (to its simplest form, irreducible - the smallest possible numerator and denominator) Sep 22 09:22 UTC (GMT)
Completely reduce (simplify) the fraction 8 / 3,105 to the lowest terms (to its simplest form, irreducible - the smallest possible numerator and denominator) Sep 22 09:22 UTC (GMT)
Completely reduce (simplify) the fraction 8 / 99 to the lowest terms (to its simplest form, irreducible - the smallest possible numerator and denominator) Sep 22 09:22 UTC (GMT)
Completely reduce (simplify) the fraction 81 / 810 to the lowest terms (to its simplest form, irreducible - the smallest possible numerator and denominator) Sep 22 09:22 UTC (GMT)
Completely reduce (simplify) the fraction 122 / 1 to the lowest terms (to its simplest form, irreducible - the smallest possible numerator and denominator) Sep 22 09:22 UTC (GMT)
Completely reduce (simplify) the fraction 16,677 / 8,341 to the lowest terms (to its simplest form, irreducible - the smallest possible numerator and denominator) Sep 22 09:22 UTC (GMT)
Completely reduce (simplify) the fraction 31,250,000 / 100,000,000,000 to the lowest terms (to its simplest form, irreducible - the smallest possible numerator and denominator) Sep 22 09:22 UTC (GMT)
Completely reduce (simplify) the fraction 56,732 / 500 to the lowest terms (to its simplest form, irreducible - the smallest possible numerator and denominator) Sep 22 09:22 UTC (GMT)
Completely reduce (simplify) the fraction 88 / 972 to the lowest terms (to its simplest form, irreducible - the smallest possible numerator and denominator) Sep 22 09:22 UTC (GMT)
The list of all the fractions that were fully reduced (simplified) to their lowest terms (to their simplest form), the smallest possible numerator and denominator

Tutoring: simplifying fractions - reducing them to the lowest terms

Steps to simplify a fraction, to reduce it to its lowest terms:

Example: reduce the fraction 315/1,155 as much as possible, simplify it to the lowest terms.

Why reducing (simplifying) fractions to lower terms?

Read the entire article >> Completely reduce (simplify) fractions to the lowest terms: Steps and Examples

Some articles on the prime numbers

What is a prime number? Definition, examples

What is a composite number? Definition, examples

The prime numbers up to 1,000

The prime numbers up to 10,000

The Sieve of Eratosthenes

The Euclidean Algorithm

Completely reduce (simplify) fractions to the lowest terms: Steps and Examples