Greatest common factor is a common factor shared by two or more numbers. Both numbers are even, so let's divide both numbers by two. We get . These are prime numbers (factors of one and itsef) in which we are done. Anytime we have two prime numbers or one prime and one composite number, we are finished. So the greatest common factor is .

Greatest common factor is a common factor shared by two or more numbers. is a multiple of , so let's divide for both numbers. We get . We are finished as these are the basic numbers. So the greatest common factor is .

Greatest common factor is a common factor shared by two or more numbers. is a prime number. is a composite number. Since we have a prime and composite number, the greatest common factor is .

Greatest common factor is a common factor shared by two or more numbers. Both numbers are even, so let's divide two for both numbers. We get . We have one prime and one composite number, so we are finished. The greatest common factor is .

Since v is divisible by 2, 3 and 15, v must be a multiple of 30. Any number that is divisible by both 2 and 15 must be divisible by their product, 30, since this is the least common multiple.

Out of all the answer choices, v + 30 is the only one that equals a multiple of 30.

We are given information that m/4 is 10 greater than m/3. We set up an equation where m/4 = m/3 + 10.

We must then give the m variables a common denominator in order to solve for m. Since 3 * 4 = 12, we can use 12 as our denominator for both m variables.

m/4 = m/3 + 10 (Multiply m/4 by 3 in the numerator and denominator.)

3m/12 = m/3 + 10 (Multiply m/3 by 4 in the numerator and denominator.)

3m/12 = 4m/12 + 10 (Subtract 4m/12 on both sides.)

-m/12 = 10 (Multiply both sides by -12.)

m = -120

-120/4 = -30 and -120/3 = -40. -30 is 10 greater than -40.

These two numbers are definitely divisible by . When we divide both numbers by , we get and remaining. Since we have a combination of a prime and composite number, then we can't find any more factors. Our answer is .

Let's do some divisibility rules. For , the sum of the digits must be divisible by .

We have:

They are both good so when we divide both numbers by , we get . Lastly they are both divisible by . So we multiply both factors to get an answer of .

Greatest common factor involves all the numbers in the set. Even though three of the numbers are divisble by , isn't. The only factor that satisfies all the numbers is .

The key here is to find the prime factorizations of both numbers and multiplying the common prime factors together:

Both prime factorizations have in common, so is our answer.