What is the HCF of 84 and 90?
HCF (Highest Common Factor) of two numbers, 84 and 90 is the highest possible number that divides the numbers 84 and 90 exactly without any remainder.
Answer: HCF of 84 and 90 is 6
Let us see how to find the HCF of 84 and 90
Explanation:
To find the HCF (Highest Common Factor) of 84 and 90, we have to determine the largest possible number which divides 84 and 90 exactly leaving the remainder as 0.
We can find the HCF by the following two methods:

Prime factorization Method

Long division Method
Methods to Find HCF of 84 and 90
Method 1: HCF of 84 and 90 by Prime Factorization
Let us represent 84 and 90 as a product of its prime numbers
Prime factorization of 84 is 2 × 2 × 3 × 7
Prime factorization of 90 is 2 × 3 × 3 × 5
Common factors = 2, 3
HCF of 84 and 90 is the product of the prime factors that are common to each of the given numbers.
HCF of 84 and 90 is 6
Method 2: HCF of 84 and 90 by Long Division

Step 1: Divide the highest number 90 by the smaller number 84 and check the remainder.

Step 2: Make the remainder of the above step as the divisor and the divisor of the above step as the dividend and perform the long division again.

Step 3: Continue till you get the remainder as 0 and HCF of 84 and 90 is the last divisor obtained.
You can find the HCF of 84 and 90 in any of the above methods but the solution will be the same.