Answer:
15, 21, 28
Explanation:
Given the distribution of points :
1, 3, 6, 10
Closely examining the distribution :
Difference between the first and second value = 3 - 1 = 2
This difference increases by one for the difference between each subsequent numbers.
The next there numbers :
1, 3, 6, 10
10 - 6 = 4 ;
10 + (4 + 1) = 15
10 + 5 = 15
15 + (5 + 1) = 21
15 + 6 = 21
21 + (6 + 1) = 28
21 + 7 = 28