Table of Contents
- Upside Down Division Method
- What’s Next?
In the previous segment, we solved examples based on the Factor tree method. In this segment, we will learn one more technique of prime factorisation, the Upside down division method.
What is the Upside down division method?
In this method of finding prime factors of a number, the quotient is written under the dividend and hence the name ‘Upside down division’.
Q. Factorise 36 into its prime factors. Solution:
The first step is to find a prime number that is an exact divisor of 36. Start with 2, move on to 3, and so on.
The digit in the units place of 36 is divisible by 2. Hence 36 is also divisible by 2. So we start with 2.
Dividing 36 by 2 will give 18 as the quotient. Since this is the upside-down division method, 18 is written below 36 as shown.
Next, find a prime number that is the exact divisor of 18. 18 is divisible by 2. So we write 2 as shown.
2 x 9 = 18. So, 9 is the quotient written below 18.