14
12-13-15 etc.... The sequence is add 1 then add 2
31
11, -10, 9
15
20
The sequence appears to alternate between adding and subtracting numbers. The pattern seems to be +11, -7, +5, -2, +6. Following this pattern, the next number in the sequence would be +3 from the previous number, which would be 21.
11
11
11.
21
15
22
What number best completes the sequence 1 1/2 5 10 1/2 18
10,20,30,20
The next number in the sequence is 27.
14