GCF of

Question

170, 238? 

Answer 1

The GCF is the product of the common prime factors in each number.

Factor each monomial and Circle the common prime factors.

The product of common prime factors, 2•17 or 34 is called the greatest common factor of 170 and 238.

 

Answer 2

Here are two more methods to find the GCF

 

Method 2: Find all factors of both numbers, pick the largest common one: 

170: 1,2,5,10,17,34,85,170 

238:1,2,7,14,17,34,119,238 

Biggest one is 34. 

 

Third method: subtract the smaller one from the bigger one until the pair is the same number. 

238- 170= 68 

New pair is 170,68. 

170-68=102. 

New pair is 102,68. 

102-68 = 34. 

New pair is 68,34. 

68-34=34. 

34 is the GCF.

 

source: https://answers.yahoo.com