Answer:
k = 1 or 2 or 5 or 10
Step-by-step explanation:
Suppose GCD is k, 2 numbers are kA and kB
LCM is k*A*B,
GCD*LCM: k*(k*A*B) = 200
k² * A*B = 200
A*B could be 1 , 2, 4, 5, 8, 10, 20, 25, 40, 50, 100, 200
k² (k is integer) could be 1, 4, 25, 100
k = 1 or 2 or 5 or 10
