ClassX Video Lessons Youtube Channel Smile and Learn English LEAST COMMON MULTIPLE ???? How to Calculate the Least Common Multiple – Math for Kids
Hello friends! Today, we’re going to learn how to find the least common multiple, or LCM for short. But first, let’s talk about what multiples are. A multiple is what you get when you multiply a number by any whole number.
Let’s look at an example: 10 is a multiple of 2 because 2 times 5 equals 10. Similarly, 15 is a multiple of 3 because 3 times 5 equals 15. Multiples are super important in math, and we use them all the time!
The least common multiple of two numbers is the smallest multiple that both numbers share. There are different ways to find the LCM, and one simple way is to list the first few multiples of each number and see which one they have in common.
Let’s find the LCM of 2 and 8 by listing their multiples:
The smallest multiple they both have is 8, so the LCM of 2 and 8 is 8!
When dealing with larger numbers, there’s another method called the common division method. This method uses prime numbers to help find the LCM.
Let’s find the LCM of 50 and 75 using the common division method:
Since 2 and 3 are prime numbers and can’t be divided further, we stop here. To find the LCM, multiply all the prime numbers we used: 5 × 5 × 2 × 3 = 150. So, the LCM of 50 and 75 is 150!
That’s all for today, everybody! Now you know how to find the least common multiple. Keep practicing, and you’ll get even better at solving math problems. See you soon!
We’ve learned so much in just one lesson! Did you know there are many more lessons out there? Imagine how much you could learn! Keep exploring and have fun with math!
Multiples Scavenger Hunt: Go on a scavenger hunt around your home or classroom to find items that come in groups. For example, look for pairs of socks, sets of crayons, or stacks of books. Count how many items are in each group and write them down. Then, try to find the least common multiple of two different groups. For instance, if you have a group of 4 crayons and a group of 6 books, list the multiples of each and find the smallest one they share.
LCM Art Project: Create a colorful poster that shows the multiples of two numbers. Pick two numbers between 1 and 10, and list their multiples up to 50. Use different colors for each number’s multiples. Once you have your lists, circle the least common multiple in a bright color. Display your artwork to show how you found the LCM!
Story Time with Multiples: Write a short story or comic strip about two characters who need to find the least common multiple to solve a problem. Maybe they are trying to meet at the same time or share something equally. Use your imagination and include the steps they take to find the LCM. Share your story with a friend or family member and explain how the characters solved their problem using math!
Here’s a sanitized version of the provided YouTube transcript:
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Hello friends! Today we’re going to learn how to find the least common multiple. To understand what this term means, we first need to review what multiples are. A multiple is the product of a number multiplied by any other whole number.
Let’s see an example: 10 is a multiple of 2 because 2 times 5 is 10. Similarly, 15 is a multiple of 3 because if we multiply 3 times 5, the product is 15. We use multiples all the time in math; they’re super important!
So, what is the least common multiple? The least common multiple of two numbers is the smallest multiple that those numbers have in common. There are many different ways of finding the least common multiple. One way is to compare the first few multiples of certain numbers.
For example, let’s find the least common multiple of 2 and 8. We’ll start by writing down the multiples of 2:
– 2 times 1 is 2
– 2 times 2 is 4
– 2 times 3 is 6
– 2 times 4 is 8
– 2 times 5 is 10
Now, let’s calculate the multiples of 8:
– 8 times 1 is 8
– 8 times 2 is 16
– 8 times 3 is 24
– 8 times 4 is 32
– 8 times 5 is 40
Now that we have the multiples of these two numbers, we can see which is the smallest multiple they have in common. The least common multiple of 2 and 8 is 8, as it is the smallest multiple that these two numbers share.
Finding the least common multiple of these two numbers is easy because they are small. However, there is another method to calculate the least common multiple that is helpful for larger numbers. It’s called the common division method.
The common division method is a simple way to find the least common multiple between two or more numbers. In this method, we divide the numbers by common prime numbers.
Let’s look at an example: we will find the least common multiple for the numbers 50 and 75. We begin by writing the numbers separated by a comma and drawing a line to the left of the first number and under both.
Next, we need to think of the smallest prime number that is a common factor of 50 and 75 and can divide them equally without a remainder. This number is called a prime factor. Since 75 is an odd number and not divisible by 2, we continue.
What about 3? 50 is not divisible by 3. The next prime number is 5, which works. We write 5 to the left of the two numbers and divide:
– 50 divided by 5 is 10
– 75 divided by 5 is 15
We write each quotient below the corresponding number, separated by a comma. Since we can divide 10 and 15 further, we continue.
What is the smallest prime number that goes into 10 and 15? That’s right, it’s 5 again. We write 5 to the left of the two numbers and divide again:
– 10 divided by 5 is 2
– 15 divided by 5 is 3
We write each quotient below the corresponding number. Since 2 and 3 cannot be divided by a common prime number and are also prime numbers, we stop dividing there.
Now we calculate the least common multiple by multiplying 5 times 5 times 2 times 3, or 5 squared times 2 times 3. The answer is 150. So, 150 is the least common multiple for 50 and 75.
That’s all for today, everybody! I hope this helps you solve future math problems. See you soon!
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