What is the greatest common factor of 117 & 351

And What is the greatest common factor of 35 & 149

So we factor out the number and find the number in both numbers so

117=3*3*13

351=3*3*13*3

so the greatest common factor of 117 and 351 is 3*3*13=117

35=7*5

149=prime=149 (prime means no whole factors)