# What is GCF of 40 and 72?

GCF of 40 and 72 is 8

#### How to find GCF of two numbers

 1.   Steps to find GCF of 40 and 72 2.   What is GCF of two numbers? 3.   What are Factors? 4.   Examples of GCF

### Example: Find gcf of 40 and 72

• Factors for 40: 1, 2, 4, 5, 8, 10, 20, 40
• Factors for 72: 1, 2, 3, 4, 6, 8, 9, 12, 18, 24, 36, 72

Hence, GCf of 40 and 72 is 8

#### Definition of GCF

Greatest common factor commonly known as GCF of the two numbers is the highest possible number which completely divides given numbers, i.e. without leaving any remainder. It is represented as GCF (40, 72).

#### Properties of GCF

• The GCF of two or more given numbers cannot be greater than any of the given number. Eg- GCF of 40 and 72 is 8, where 8 is less than both 40 and 72.
• GCF of two consecutive numbers is always 1.
• The product of GCF and LCM of two given numbers is equal to the product of two numbers.
• The GCF of two given numbers where one of them is a prime number is either 1 or the number itself.

#### What are factors?

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

#### Properties of Factors

• Each number is a factor of itself. Eg. 40 and 72 are factors of themselves respectively.
• 1 is a factor of every number. Eg. 1 is a factor of 40 and also of 72.
• Every number is a factor of zero (0), since 40 x 0 = 0 and 72 x 0 = 0.
• Every number other than 1 has at least two factors, namely the number itself and 1.
• Every factor of a number is an exact divisor of that number, example 1, 2, 4, 5, 8, 10, 20, 40 are exact divisors of 40 and 1, 2, 3, 4, 6, 8, 9, 12, 18, 24, 36, 72 are exact divisors of 72.
• Factors of 40 are 1, 2, 4, 5, 8, 10, 20, 40. Each factor divides 40 without leaving a remainder.
Simlarly, factors of 72 are 1, 2, 3, 4, 6, 8, 9, 12, 18, 24, 36, 72. Each factor divides 72 without leaving a remainder.
• Every factor of a number is less than or equal to the number, eg. 1, 2, 4, 5, 8, 10, 20, 40 are all less than or equal to 40 and 1, 2, 3, 4, 6, 8, 9, 12, 18, 24, 36, 72 are all less than or equal to 72.

#### Steps to find Factors of 40 and 72

• Step 1. Find all the numbers that would divide 40 and 72 without leaving any remainder. Starting with the number 1 upto 20 (half of 40) and 1 upto 36 (half of 72). The number 1 and the number itself are always factors of the given number.
40 ÷ 1 : Remainder = 0
72 ÷ 1 : Remainder = 0
40 ÷ 2 : Remainder = 0
72 ÷ 2 : Remainder = 0
40 ÷ 4 : Remainder = 0
72 ÷ 3 : Remainder = 0
40 ÷ 5 : Remainder = 0
72 ÷ 4 : Remainder = 0
40 ÷ 8 : Remainder = 0
72 ÷ 6 : Remainder = 0
40 ÷ 10 : Remainder = 0
72 ÷ 8 : Remainder = 0
40 ÷ 20 : Remainder = 0
72 ÷ 9 : Remainder = 0
40 ÷ 40 : Remainder = 0
72 ÷ 12 : Remainder = 0
72 ÷ 18 : Remainder = 0
72 ÷ 24 : Remainder = 0
72 ÷ 36 : Remainder = 0
72 ÷ 72 : Remainder = 0

Hence, Factors of 40 are 1, 2, 4, 5, 8, 10, 20, and 40

And, Factors of 72 are 1, 2, 3, 4, 6, 8, 9, 12, 18, 24, 36, and 72

#### Examples of GCF

Sammy baked 40 chocolate cookies and 72 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 40 and 72.
GCF of 40 and 72 is 8.

A class has 40 boys and 72 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 40 and 72. Hence, GCF of 40 and 72 is 8.

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(40, 72) = ( 40 * 72 ) / LCM(40, 72) = 8.

What is the GCF of 40 and 72?

GCF of 40 and 72 is 8.

Mary has 40 blue buttons and 72 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 40 and 72. Hence, the GCF of 40 and 72 or the greatest arrangement is 8.

Kamal is making identical balloon arrangements for a party. He has 40 maroon balloons, and 72 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 40 and 72. So the GCF of 40 and 72 is 8.

Kunal is making baskets full of nuts and dried fruits. He has 40 bags of nuts and 72 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 40 and 72. So the GCF of 40 and 72 is 8.

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 40 bus tickets and 72 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 40 and 72. Hence, GCF of 40 and 72 is 8.