What is GCF of 13 and 21?

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GCF of 13 and 21 is 1

How to find GCF of two numbers

Steps to find GCF of 13 and 21

Find all the numbers that would divide 13 and 21 without leaving any remainder as explained in factors below.
Find the greatest common factor from the list of factors for 13 and 21, and read off the answer!

Example: Find gcf of 13 and 21

Factors for 13: 1, 13
Factors for 21: 1, 3, 7, 21

Hence, GCf of 13 and 21 is 1

What does GCF mean in mathematics?

Greatest Common Fcator (GCF) or also sometimes written as greates common divisor is the largest number that can evenly divide the given two numbers. GCF is represented as GCF (13, 21).

Properties of GCF

The GCF of two or more given numbers is always less than the given numbers. Eg- GCF of 13 and 21 is 1, where 1 is less than both the numbers.
If the given numbers are consecutive than GCF is always 1.
Product of two numbers is always equal to the product of their GCF and LCM.
The GCF of two given numbers where one of them is a prime number is either 1 or the number itself.

What is the definition of factors?

In mathematics, factors are number, algebraic expressions which when multiplied together produce desired product. A factor of a number can be positive or negative.

Properties of Factors

Every factor of a number is an exact divisor of that number, example 1, 13 are exact divisors of 13 and 1, 3, 7, 21 are exact divisors of 21.
Every number other than 1 has at least two factors, namely the number itself and 1.
Each number is a factor of itself. Eg. 13 and 21 are factors of themselves respectively.
1 is a factor of every number. Eg. 1 is a factor of 13 and also of 21.

Steps to find Factors of 13 and 21

Step 1. Find all the numbers that would divide 13 and 21 without leaving any remainder. Starting with the number 1 upto 6 (half of 13) and 1 upto 10 (half of 21). The number 1 and the number itself are always factors of the given number.

13 ÷ 1 : Remainder = 0

21 ÷ 1 : Remainder = 0

13 ÷ 13 : Remainder = 0

21 ÷ 3 : Remainder = 0

21 ÷ 7 : Remainder = 0

21 ÷ 21 : Remainder = 0

Hence, Factors of 13 are 1 and 13

And, Factors of 21 are 1, 3, 7, and 21

Examples of GCF

Sammy baked 13 chocolate cookies and 21 fruit and nut cookies to package in plastic containers for her friends at college. She wants to divide the cookies into identical boxes so that each box has the same number of each kind of cookies. She wishes that each box should have greatest number of cookies possible, how many plastic boxes does she need?

Since Sammy wants to pack greatest number of cookies possible. So for calculating total number of boxes required we need to calculate the GCF of 13 and 21.
GCF of 13 and 21 is 1.

A class has 13 boys and 21 girls. A choir teacher wants to form a choir team from this class such that the students are standing in equal rows also girls or boys will be in each row. Teacher wants to know the greatest number of students that could be in each row, can you help him?

To find the greatest number of students that could be in each row, we need to find the GCF of 13 and 21. Hence, GCF of 13 and 21 is 1.

What is the difference between GCF and LCM?

Major and simple difference betwen GCF and LCM is that GCF gives you the greatest common factor while LCM finds out the least common factor possible for the given numbers.

What is the relation between LCM and GCF (Greatest Common Factor)?

GCF and LCM of two numbers can be related as GCF(13, 21) = ( 13 * 21 ) / LCM(13, 21) = 1.

What is the GCF of 13 and 21?

GCF of 13 and 21 is 1.

Mary has 13 blue buttons and 21 white buttons. She wants to place them in identical groups without any buttons left, in the greatest way possible. Can you help Mary arranging them in groups?

Greatest possible way in which Mary can arrange them in groups would be GCF of 13 and 21. Hence, the GCF of 13 and 21 or the greatest arrangement is 1.

Kamal is making identical balloon arrangements for a party. He has 13 maroon balloons, and 21 orange balloons. He wants each arrangement tohave the same number of each color. What is the greatest number of arrangements that he can make if every balloon is used?

The greatest number of arrangements that he can make if every balloon is used would be equal to GCF of 13 and 21. So the GCF of 13 and 21 is 1.

Kunal is making baskets full of nuts and dried fruits. He has 13 bags of nuts and 21 bags of dried fruits. He wants each basket to be identical, containing the same combination of bags of nuts and bags of driesn fruits, with no left overs. What is the greatest number of baskets that Kunal can make?

the greatest number of baskets that Kunal can make would be equal to GCF of 13 and 21. So the GCF of 13 and 21 is 1.

To energize public transportation, Abir needs to give a few companions envelopes with transport tickets, and metro tickets in them. On the off chance that he has 13 bus tickets and 21 metro tickets to be parted similarly among the envelopes, and he need no tickets left. What is the greatest number of envelopes Abir can make?

To make the greatest number of envelopes Abir needs to find out the GCF of 13 and 21. Hence, GCF of 13 and 21 is 1.