What is the greatest common factor of 42, 126, and 210

Expert Answers info

justaguide eNotes educator | Certified Educator

calendarEducator since 2010

write12,544 answers

starTop subjects are Math, Science, and Business

To find the greatest common factor of 42, 126, and 210, we find the prime factors of the 3 numbers.

42 = 7 * 3 * 2

126 = 2 * 7 * 3 * 3

and 210 = 5 * 2 * 7 * 3

Now taking the common terms we have 7 , 3 and 2

7*3*2 = 42.

Therefore the greatest common factor or GCF  is 42

check Approved by eNotes Editorial
hala718 eNotes educator | Certified Educator

calendarEducator since 2008

write3,662 answers

starTop subjects are Math, Science, and Social Sciences

Given the numbers 42, 126, and 210

We need to find the greatest common factor ( GCF)

First we will factor each numbers.

==> 42 = 2*3*7

==> 126 = 2*3*3*7

==> 210 = 2*3*5*7

Now we will determine the common factors between all three numbers and multiply.

We notice that the common factors are 2 , 3 and 7.

Then the greatest common factor = 2*3*7 = 42

check Approved by eNotes Editorial