17, 34, 51, 68, 85, basically up to 17 x 5
99
There are fourteen multiples of seven that are under 100.
21,42,63,84
There are ten different integral multiples of 10 that are equal or less than 100.
The multiples of 5 that are also multiples of 6 are multiples of their LCM. The LCM of 5 and 6 is 30, so the question becomes which multiples of 30 are less than 100? The solution is the numbers: 30, 60, 90
33
9,18,27,36,45,54,63,72,81,90,99
21,42,63,84
12,24,36,48,60,72,84,96
44 and 88 are the only common multiples of 4 and 11 that are less than 100
Multiples of 50 that are less than 200 are 100 and 150.
14 of them.