To get from 8 to 11 we have to add 3
To get from 11 to 14 we have to add 3
The next number will be found by adding 3 to 14, getting 17
8                <--  8 is not divisible by 10
8+11 = 19        <-- 19 is not divisible by 10
8+11+14 = 33     <-- 33 is not divisible by 10
8+11+14+17 = 50  <-- 50 IS DIVISIBLE BY 10.
So adding the very next number, 17, gives 50, a multiple of 10.
Edwin