What is GCF of 9 and 15?

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GCF of 9 and 15 is 3

How to find GCF of two numbers

Steps to find GCF of 9 and 15

Find all the numbers that would divide 9 and 15 without leaving any remainder as explained in factors below.
Find the greatest common factor from the list of factors for 9 and 15, and read off the answer!

Example: Find gcf of 9 and 15

Factors for 9: 1, 3, 9
Factors for 15: 1, 3, 5, 15

Hence, GCf of 9 and 15 is 3

How do you explain GCF in mathematics?

GCF or greatest common factor of two or more numbers is defined as largest possible number or integer which is the factor of all given number or in other words we can say that largest possible common number which completely divides the given numbers. GCF of two numbers can be represented as GCF (9, 15).

Properties of GCF

The GCF of two or more given numbers is always less than the given numbers. Eg- GCF of 9 and 15 is 3, where 3 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.

How can we define factors?

In mathematics, a factor is a number which divides into another number exactly, without leaving any remainder. A factor of a number can be positive of negative.

Properties of Factors

Every factor of a number is an exact divisor of that number, example 1, 3, 9 are exact divisors of 9 and 1, 3, 5, 15 are exact divisors of 15.
Every number other than 1 has at least two factors, namely the number itself and 1.
Each number is a factor of itself. Eg. 9 and 15 are factors of themselves respectively.
1 is a factor of every number. Eg. 1 is a factor of 9 and also of 15.

Steps to find Factors of 9 and 15

Step 1. Find all the numbers that would divide 9 and 15 without leaving any remainder. Starting with the number 1 upto 4 (half of 9) and 1 upto 7 (half of 15). The number 1 and the number itself are always factors of the given number.

9 ÷ 1 : Remainder = 0

15 ÷ 1 : Remainder = 0

9 ÷ 3 : Remainder = 0

15 ÷ 3 : Remainder = 0

9 ÷ 9 : Remainder = 0

15 ÷ 5 : Remainder = 0

15 ÷ 15 : Remainder = 0

Hence, Factors of 9 are 1, 3, and 9

And, Factors of 15 are 1, 3, 5, and 15

Examples of GCF

Sammy baked 9 chocolate cookies and 15 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 9 and 15.
GCF of 9 and 15 is 3.

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(9, 15) = ( 9 * 15 ) / LCM(9, 15) = 3.

What is the GCF of 9 and 15?

GCF of 9 and 15 is 3.

Ram has 9 cans of Pepsi and 15 cans of Coca Cola. He wants to create identical refreshment tables that will be organized in his house warming party. He also doesn't want to have any can left over. What is the greatest number of tables that Ram can arrange?

To find the greatest number of tables that Ram can stock we need to find the GCF of 9 and 15. Hence GCF of 9 and 15 is 3. So the number of tables that can be arranged is 3.

Rubel is creating individual servings of starters for her birthday party. He has 9 pizzas and 15 hamburgers. He wants each serving to be identical, with no left overs. Can you help Rubel in arranging the same in greatest possible way?

The greatest number of servings Rubel can create would be equal to the GCF of 9 and 15. Thus GCF of 9 and 15 is 3.

Ariel is making ready to eat meals to share with friends. She has 9 bottles of water and 15 cans of food, which she would like to distribute equally, with no left overs. What is the greatest number of boxes Ariel can make?

The greatest number of boxes Ariel can make would be equal to GCF of 9 and 15. So the GCF of 9 and 15 is 3.

Mary has 9 blue buttons and 15 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 9 and 15. Hence, the GCF of 9 and 15 or the greatest arrangement is 3.

Kamal is making identical balloon arrangements for a party. He has 9 maroon balloons, and 15 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 9 and 15. So the GCF of 9 and 15 is 3.