Created By : Jatin Gogia
Reviewed By : Rajasekhar Valipishetty
Last Updated : Apr 06, 2023
HCF Calculator using the Euclid Division Algorithm helps you to find the Highest common factor (HCF) easily for 85, 51, 21 i.e. 1 the largest integer that leaves a remainder zero for all numbers.
HCF of 85, 51, 21 is 1 the largest number which exactly divides all the numbers i.e. where the remainder is zero. Let us get into the working of this example.
Consider we have numbers 85, 51, 21 and we need to find the HCF of these numbers. To do so, we need to choose the largest integer first and then as per Euclid's Division Lemma a = bq + r where 0 ≤ r ≤ b
Highest common factor (HCF) of 85, 51, 21 is 1.
HCF(85, 51, 21) = 1
Highest common factor or Highest common divisor (hcd) can be calculated by Euclid's algotithm.
Highest common factor (HCF) of 85, 51, 21 is 1.
Step 1: Since 85 > 51, we apply the division lemma to 85 and 51, to get
85 = 51 x 1 + 34
Step 2: Since the reminder 51 ≠ 0, we apply division lemma to 34 and 51, to get
51 = 34 x 1 + 17
Step 3: We consider the new divisor 34 and the new remainder 17, and apply the division lemma to get
34 = 17 x 2 + 0
The remainder has now become zero, so our procedure stops. Since the divisor at this stage is 17, the HCF of 85 and 51 is 17
Notice that 17 = HCF(34,17) = HCF(51,34) = HCF(85,51) .
We can take hcf of as 1st numbers and next number as another number to apply in Euclidean lemma
Step 1: Since 21 > 17, we apply the division lemma to 21 and 17, to get
21 = 17 x 1 + 4
Step 2: Since the reminder 17 ≠ 0, we apply division lemma to 4 and 17, to get
17 = 4 x 4 + 1
Step 3: We consider the new divisor 4 and the new remainder 1, and apply the division lemma to get
4 = 1 x 4 + 0
The remainder has now become zero, so our procedure stops. Since the divisor at this stage is 1, the HCF of 17 and 21 is 1
Notice that 1 = HCF(4,1) = HCF(17,4) = HCF(21,17) .
Here are some samples of HCF using Euclid's Algorithm calculations.
1. What is the Euclid division algorithm?
Answer: Euclid's Division Algorithm is a technique to compute the Highest Common Factor (HCF) of given positive integers.
2. what is the HCF of 85, 51, 21?
Answer: HCF of 85, 51, 21 is 1 the largest number that divides all the numbers leaving a remainder zero.
3. How to find HCF of 85, 51, 21 using Euclid's Algorithm?
Answer: For arbitrary numbers 85, 51, 21 apply Euclid’s Division Lemma in succession until you obtain a remainder zero. HCF is the remainder in the last but one step.