It depends on the function that is used to generate the sequence - and there are infinitely many of them.
One possible generators is
t(n) = 10n2 - 90n + 200 where n = 1, 2, 3, ...
If that is the case, the next number is 0.
But, if I wanted to have the next number as 20, I could re-define the generating function as:
t(n) = (10n3 - 30n2 - 160n + 540)/3 where n = 1, 2, 3, etc.
Give me any fourth number and I can give you a cubic polynomial that will generate that sequence.
10 The sequence is given by xn = 60/n
120
Those are the factors of the number 60, in descending order. The next factor is 10.
480, 96, 960
240
10 The sequence is given by xn = 60/n
120
20
720
120, 960...
2x6 is 12 Add a zero (the zero from 20) and you have: 120
Those are the factors of the number 60, in descending order. The next factor is 10.
The least common multiple of 20, 40, and 60 is 120.
480, 96, 960
10,20,30,20
60 + 20% = 60*120/100 = 72
The LCM of 20 and 60 is 60.