Question

Find the GCD and the LCM of each of the following. (Do not compute the products)
A. 10!, 11!
B. 10!, 10!+1
C. PQR, QRS ( where p,q,r,s are prime numbers)
D.2^10, 2^8

Answer 1

Write the factors of each, and the answer practically jumps off the page at you.

Answer 2

The GCD is the largest combination of factors shared by both numbers.

The LCM is the smallest combination of factors that includes all the factors in both numbers.