GCD of 2, 7 and 8
To use the GCD / GCF / HCF Calculator below just enter a set of numbers separated by commas (,).
GCF Calculator
Enter values separeted by commas: Ex.: 2,4,8; 3,6 etc. 
Detailed Answer: Greatest Common Divisor explained here

You have reached us maybe looking for answers to the questions like: GCD of 2, 7 and 8 or what is the highest common factor (HCF) of 2, 7 and 8?
What is the GCF of 2, 7 and 8?
The first step to find the gcf of 2, 7 and 8 is to list the factors of each number. The factors of 2 are 1 and 2. The factors of 7 are 1 and 7. The factors of 8 are 1, 2, 4 and 8. So, the Greatest Common Factor for these numbers is 1 because it divides all them without a remainder. Read more about Common Factors below.
See also:
How to find the Greatest Common Factor
GCF example:
The first step is to find all divisors of each number. For instance, let us find the gcf(2,7,8).
In this case we have:
 The factors of 2 (all the whole numbers that can divide the number without a remainder) are 1 and 2;
 The factors of 7 are 1 and 7;
 The factors of 8 are 1, 2, 4 and 8.
The second step is to analyze which are the common divisors. It is not difficult to see that the 'Greatest Common Factor' or 'Divisor' for 2, 7 and 8 is 1. The GCF is the largest common positive integer that divides all the numbers (2,7,8) without a remainder.
The GCF is also known as:
 Greatest common divisor (gcd);
 Highest common factor (hcf);
 Greatest common measure (gcm), or
 Highest common divisor
Greatest Common Factor Calculator
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