Greatest Common Divisor (GCD) of 6, 18 and 30 The Greatest Common Divisor (GCD) of 6, 18 and 30 is the largest positive integer that equally divides all three numbers: 6, 18 and 30. Mathematically, the problem we are solving is:

GCD(6,18,30)

To solve the problem, we will list all the positive integers (divisors) that can be divided into 6, 18 and 30. We will then compare the lists of divisors to find the greatest divisor they have in common.

Divisors of 6:
1, 2, 3, and 6.

Divisors of 18:
1, 2, 3, 6, 9, and 18.

Divisors of 30:
1, 2, 3, 5, 6, 10, 15, and 30.

When we compare the lists of divisors above, we see that the largest number they have in common is 6. Thus, the Greatest Common Divisor (GCD) of 6, 18 and 30 is:

GCD(6,18,30) = 6

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Greatest Common Divisor (GCD) of 6, 18 and 31
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