Question

solve series
1,6,15,_______,45,66,91​

Answer 1

Answer:

The pattern is + 5, + 9, ..., + 21, + 25

.'. Missing number = 15 + 13 = 28.

Step-by-step explanation:

Answer 2

Answer:

28

Step-by-step explanation:

1 + 5 = 6

6 + 9 = 15

15 + 13 = 28

28 + 17 = 45

45 + 21 = 66

66 + 25 = 91