Factors and Multiples for class 4

What are Factors and Multiples?

Factors and multiples are fundamental concepts in mathematics that play a significant role in solving various problems. Let’s understand each of these concepts in detail:

Factors: A factor of a number is a whole number that divides the given number exactly without leaving a remainder. In simpler terms, factors are numbers that can divide into a given number without any remainder.

Examples:

Let’s consider the number 12. The factors of 12 are 1, 2, 3, 4, 6, and 12, as these numbers can divide 12 without leaving a remainder. For instance, 2 is a factor of 12 because 12 divided by 2 equals 6.

Multiples: A multiple of a number is a result obtained by multiplying the given number by any whole number. In other words, multiples are numbers that can be obtained by multiplying a given number with other whole numbers.

Examples:

To find the multiples of 5, we multiply 5 by different whole numbers. The multiples of 5 are 5, 10, 15, 20, and so on, as each of these numbers is obtained by multiplying 5 by 1, 2, 3, 4, respectively.

Finding Factors:

To find factors of a number, we can follow these steps:

To find factors, we need to identify which numbers can divide a given number evenly. Here are the steps to find factors:

  • Start with the number 1, as every number is divisible by 1.
  • Check divisibility by other integers until reaching the number itself.
  • Factors always come in pairs, with the pair of the factor multiplying to give the original number.

Example: Find the factors of 24.

Factors of 24: 1, 2, 3, 4, 6, 8, 12, 24

Prime and Composite Numbers:

Prime Numbers: A prime number is a number greater than 1 that has exactly two factors: 1 and the number itself.

Example: 2, 3, 5, 7, 11, 13, etc.

Composite Numbers: A composite number is a number greater than 1 that has more than two factors.

Example: 4, 6, 8, 9, 10, 12, etc.

Understanding Multiples:

To find multiples of a number, we can multiply the number by different whole numbers.

Example: Find the first five multiples of 5.

Multiples of 5: 5, 10, 15, 20, 25

Relationship between Factors and Multiples:

If a number ‘a’ is a factor of another number ‘b,’ then ‘b’ will be a multiple of ‘a.’

For example, if 3 is a factor of 12, then 12 is a multiple of 3 (3 x 4 = 12).

Common Factors and Greatest Common Factor (GCF):

Common factors are the factors that two or more numbers have in common. The largest among these common factors is called the Greatest Common Factor (GCF).

Example: Find the GCF of 24 and 36.

Factors of 24: 1, 2, 3, 4, 6, 8, 12, 24
Factors of 36: 1, 2, 3, 4, 6, 9, 12, 18, 36

Common factors: 1, 2, 3, 4, 6, 12
GCF: 12

Common Multiples and Least Common Multiple (LCM):

Common multiples are the multiples that two or more numbers have in common. The smallest among these common multiples is called the Least Common Multiple (LCM).

Example: Find the LCM of 4 and 6.

Multiples of 4: 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, …
Multiples of 6: 6, 12, 18, 24, 30, 36, 42, 48, …

Common multiples: 12, 24, 36, 48, …
LCM: 12

Real-World Applications:

Let’s explore some everyday situations where these mathematical concepts come into play:

a) Baking Cupcakes: When baking cupcakes for a party, understanding multiples helps you determine the number of cupcakes to bake to serve a specific number of guests.

For example, if you have a recipe to make 12 cupcakes but need to serve 24 guests, you can simply make the recipe twice to have enough cupcakes for everyone.

b) Dividing Chocolates: Imagine you have a box of chocolates with 36 chocolates, and you want to distribute them equally among your 6 friends. Understanding factors helps you realize that 36 is divisible by 6 (6 x 6 = 36), ensuring each friend gets an equal share of chocolates.

c) Gardening with Pots: Suppose you have a collection of 15 flowerpots, and you want to arrange them in rows with an equal number of pots in each row. Recognizing factors helps you find that 15 can be arranged in rows of 3 pots (3 x 5 = 15), making your garden display visually appealing.

d) Scheduling Breaks: During study sessions, understanding multiples can help you plan breaks effectively. If you study for 45 minutes and then take a 15-minute break, you have a multiple of 15, making it easier to manage your time efficiently.

e) Arranging Books on Shelves: If you have a collection of books and several bookshelves, understanding multiples can help you decide how to organize the books to fill the shelves most effectively, ensuring efficient use of space.

f) Sports Teams Formation: In sports, coaches may use factors to form teams with an equal number of players or to create small-sided games during practice, promoting fair play and balanced training.

Real-life situations show that factors and multiples are not only ideas in math, but they are also useful in our daily lives.