IMO Practice Test — Prime Factorization, LCM, GCF

6 Questions • 25 min • Olympiad level

25:00
Question 1 of 6 hard
The GCF of two numbers is 6 and their LCM is 72. One number is 18. Find the other.
24
36
48
54
Explanation: a×b=GCF×LCM, 18×b=6×72=432, b=432÷18=24