2.8 - 2.3 = 0.5
28
Halfway between 18 and 28 is (18 + 28) ÷ 2 = 23.
The distance between these two points is 23.
51-23 = 28
37, this sequence counts up from 5 the difference between 2 and 7. the difference between 20 and 28 is 8 making the next number 9, and 28 and 9 = 37.
28
Halfway between 18 and 28 is (18 + 28) ÷ 2 = 23.
The difference is... 25
23 is the only prime number between 20 and 28.
28
28
17.
67
23
17...
23
It is: 28