Find GCD from Prime Factorizations: Reducing Fractions

  • Context: Undergrad 
  • Thread starter Thread starter Holocene
  • Start date Start date
  • Tags Tags
    Fractions
Join the discussion
Registration is free. Ask a follow-up in this thread, or start your own.
1 reply · 2K views
Holocene
Messages
237
Reaction score
0
Is there any way to derive the greatest common divisor from the prime factorizations of the numerator and denominator?


For instance:

[tex]\displaystyle{\frac{48}{150} = \frac{ 2 * 2 * 2 * 2 * 3}{2 * 3 * 5 * 5}}[/tex]

The GCD = 6 in this example, but is there any way to determine that from the prime factorizations alone?
 
Mathematics news on Phys.org
Holocene said:
Is there any way to derive the greatest common divisor from the prime factorizations of the numerator and denominator?

Yes, that's the easiest (if not fastest) way. Just choose pairs of identical prime factors until none are left that match, then multiply the primes together.