The greatest common multiple of any set of integers is infinite.
28
There are five: 105, 126, 147, 168 and 189.
21,42,64,86,108,130,152,174,196,218They are 21, 42, 63, 84, 105, 126, 147, 168, 189, 210.
189 = 3 x 3 x 3 x 7; 105 = 3 x 5 x 7. Common factors are 3 and 7 so LCM = product /HCF ie 189 x 105/21 = 945
21, 42, 63, 84, 105,126, 147, 168, 189, 210 :)
21, 42, 63, 84, 105, 126, 147, 168, 189, 210.
The GCF is 21.
21, 42, 63, 84, 105, 126, 147, 168, 189, 210, 231, . . .
42 63 84 105 126 147 168 189 210 and so on ...
21, 42, 63, 84, 105, 126, 147, 168, 189, 210
21, 42, 63, 84, 105, 126, 147, 168, 189, 210
21, 42, 63, 84, 105, 126, 147, 168, 189, 210