36
6 12 9 18 15 30 27 54 51
9 243 - 81 = 162 81 - 27 = 54 162 = 54 * 3 54 = 18 * 3 27 - 18 = 9
729
Next number= 27 X 3 = 81.
The number 7 comes next.
81
27 times 3 = 81
21-3=18 18/2=9 9*3=27 that is the pattern so after the 36 it should be 33
9,18,27,36,45,54
the next multiple of 9 is 18, 27, 36, 45, 54, 63, 72, 81.....
6
9, 18 and 27 are three numbers that have a GCF of 9