prime factorisation of 90 is
What is the prime factorization of 90?
Answer:
The prime factorization of a number is the process of breaking it down into its basic building blocks or prime numbers. A prime number is a number greater than 1 that has no divisors other than 1 and itself.
For the number 90, we can find its prime factorization by following these steps:
-
Start with the smallest prime number, which is 2.
- Check if 90 is divisible by 2. Since 90 is even, it is divisible by 2.
- Divide 90 by 2:
[
90 \div 2 = 45
] - So, the first prime factor is 2.
-
Move to the next smallest prime number, which is 3.
- Check if 45 is divisible by 3. Since the sum of the digits (4 + 5 = 9), and 9 is divisible by 3, 45 is also divisible by 3.
- Divide 45 by 3:
[
45 \div 3 = 15
] - Hence, the next prime factor is 3.
-
Continue with the prime number 3 (since 15 is also divisible by 3).
- Divide 15 by 3:
[
15 \div 3 = 5
] - This gives another factor of 3.
- Divide 15 by 3:
-
Now we are left with 5, which is itself a prime number.
Thus, the prime factorization of 90 is:
[
90 = 2 \times 3 \times 3 \times 5
]
This can also be written using exponents for any repeated factors:
[
90 = 2 \times 3^2 \times 5
]
So, the prime factors of 90 are: 2, 3, and 5.