The year 8s and I have been focusing on a topic called ‘prime factorisation’. Our learning intention is to learn what is a prime, a factor, and HCF, and how you can solve questions when it comes to these.
On guided practice we had to find factors of numbers, how many prime numbers there are, and stating whether it is a prime or composite. A prime number can only be divided by 1 and itself. However, a composite number can be divided by other numbers; not only 1 and itself. This part made me feel calm, because it wasn’t stressing.
Therefore, we moved on to independent practice, where we used factor trees to break down composite numbers into their prime factors.
For example: to find the prime numbers of 18, we split the number into 2 sections making it 9 x 2 . Since 9 is a composite number and we are looking for primes, we break it down further into 3 x 3.
Now all the numbers are prime we have to do is compile all the prime numbers in that whole equation. So the final answer is 2 and 3, you can also say it as 3 x 3 x 2 or 3 to the power of 2 x 2.
When you see it explained it looks confusing, but it’s really easy with practice!
Lastly, on extended practice, it introduced us to HCF (highest common factor).
For example; to find the HCF of 24 and 40 we first had to list down all the factors of both numbers.
24: 1, 2, 3, 4, 6, 8, 12, 24
40: 1, 2, 4, 5, 8, 10, 20, 40
Next, we had to find what numbers appear in both. 1, 2 , 4, and 8 are factors of both 24 and 40. The highest of these is 8, therefore the HCF is 8.
Altogether, I found this topic enjoyable and managable. Understanding prime factorisation and HCF had helped me improve my problem solving skills, and I can see how it could be useful in future math.