Question

Find the next three terms in the sequence.
1, 3, 6, 10, 15, ...

Answer 1

21,28,36

Explanation:

+2,+3,+4,+5,+6,+7,+8,...

Answer 2

21, 28, 36

Explanation:

1 + 2 = 3

3 + 3 = 6

6 + 4 = 10

10 + 5 = 15

Next three terms,

15 + 6 = 21

21 + 7 = 28

28 + 8 = 36.