The number that is halfway between to others is their average value, that is, their sum divided by 2.
(6 +24)/2 = 30/2 = 15
15 is halfway between 6 and 24.
This is 4x=2x-2 as a graph
Sent a picture of the solution to the problem (s).
29000? .... what exactly are you supposed to be finding
Let me know if you have any questions!