Answer:
They are all multiples of 9
Explanation:
You need to find the greatest common factor of each one. When you do, the 9 is the biggest one. The multiples of 9 are: 9,18,27,36 which includes all of the numbers of flowers.
18 = 1,2,3,6,9,18
27=1,3,9,27
36=1,2,3,4,6,9,12,18,36